@misc{orphanBitcoin,
  title = {{Orphan Blocks}},
  url = "https://bitcoin.org/en/developer-guide#orphan-blocks",
  year = "2017",
  month = "September",
}

@inproceedings{Castro_Liskov_1999_pbft,
  title = {{Practical Byzantine Fault Tolerance}},
  author = {{Miguel Castro and Barbara Liskov}},
  url = "http://pmg.lcs.mit.edu/papers/osdi99.pdf",
  year = "1999",
  month = "February",
  booktitle = {{Proceedings of the Third Symposium on Operating Systems Design and Implementation}},
  address = "New Orleans, USA",
}

@article{Fischer_Lynch_Paterson_FLP_Impossibility_1985,
  title = {{Impossibility of Distributed Consensus with One Faulty Process}},
  author = "Michael J. Fischer and Nancy A. Lynch and Michael S. Paterson",
  url = "https://groups.csail.mit.edu/tds/papers/Lynch/jacm85.pdf",
  journal = {{Journal of the Assccktion for Computing Machinery}},
  volume = "32", 
  number = "2",
  year = "1985",
  month = "April",
  pages = "374-382",
}

@MISC{GHOST,
  TITLE = {Secure High-Rate Transaction Processing in Bitcoin},
  author = {Yonatan Sompolinsky and Aviv Zohar},
  URL = {https://eprint.iacr.org/2013/881.pdf},
  YEAR = {2013},
  Month = {12},
}

@MISC{nakamoto,
  TITLE = {Bitcoin: A Peer-to-Peer Electronic Cash Systems},
  author = {Satoshi Nakamoto},
  URL = {https://bitcoin.org/bitcoin.pdf},
  YEAR = {2008},
  Month = {11},
}

@article{paxos,
  title={Paxos Made Moderately Complex},
  author = "ROBBERT VAN RENESSE and DENIZ ALTINBUKEN",
  year = "2015",
  month = "April",
  doi = "http://dx.doi.org/10.1145/2673577",
  journal = "ACM Comput. Surv.",
  volume = "47",
  number = "3",
  address = "New York, NY, USA",
  note = "Article no. 42",
  url={http://www.cs.cornell.edu/courses/cs7412/2011sp/paxos.pdf},
}

@article{lamport_1998,
  title={The part-time parliament},
  volume={16},
  DOI={10.1145/279227.279229},
  number={2},
  journal={ACM Transactions on Computer Systems},
  author={Lamport, Leslie},
  year={1998},
  month={Jan},
  pages={133–169}
}

@INPROCEEDINGS{castro1999practical,
  AUTHOR = {Miguel Castro and Barbara Liskov and et. al},
  BOOKTITLE = {Proceedings of the Third Symposium on Operating Systems Design and Implementation},
  EDITOR = {Paul J. Leach and Margo Seltzer},
  LOCATION = {New Orleans},
  MONTH = {February},
  PAGES = {173--186},
  TITLE = {Practical Byzantine fault tolerance},
  VOLUME = {99},
  YEAR = {1999},
}


@ARTICLE{eyal2013,
  author    = {Ittay Eyal and
               Emin G{\"{u}}n Sirer},
  title     = {Majority is not Enough: Bitcoin Mining is Vulnerable},
  journal   = {CoRR},
  volume    = {abs/1311.0243},
  year      = {2013},
  url       = {http://arxiv.org/abs/1311.0243},
  timestamp = {Wed, 07 Jun 2017 14:41:57 +0200},
  biburl    = {http://dblp.uni-trier.de/rec/bib/journals/corr/EyalS13},
  bibsource = {dblp computer science bibliography, http://dblp.org}
}

@MISC{bitcoinwikipos,
  TITLE = {Bitcoin Wiki: Proof of Stake, Cunicula's Implementation and Meni's implementation},
  URL = {https://en.bitcoin.it/wiki/Proof_of_Stake#Cunicula.27s_Implementation_of_Mixed_Proof-of-Work_and_Proof-of-Stake},
  YEAR = {2017},
}

@MISC{slasher,
  AUTHOR = {Vitalik Buterin},
  TITLE = {Slasher: A Punitive Proof-of-Stake Algorithm},
  URL = {https://blog.ethereum.org/2014/01/15/slasher-a-punitive-proof-of-stake-algorithm/},
  YEAR = {2014},
}

@ARTICLE{sompolinsky2013accelerating,
  AUTHOR = {Sompolinsky, Yonatan and Zohar, Aviv},
  JOURNALTITLE = {IACR Cryptology ePrint Archive},
  NUMBER = {881},
  TITLE = {Accelerating Bitcoin's Transaction Processing. Fast Money Grows on Trees, Not Chains.},
  VOLUME = {2013},
  YEAR = {2013},
}

@MISC{kwon2014tendermint,
  AUTHOR = {Kwon, Jae},
  TITLE = {Tendermint: Consensus without mining},
  URL = {https://tendermint.com/static/docs/tendermint.pdf},
  YEAR = {2014},
}

@ARTICLE{monderer1996potential,
  AUTHOR = {Monderer, Dov and Shapley, Lloyd S},
  JOURNALTITLE = {Games and economic behavior},
  NUMBER = {1},
  PAGES = {124--143},
  TITLE = {Potential games},
  VOLUME = {14},
  YEAR = {1996},
}

@MISC{vasin2014blackcoin,
  AUTHOR = {Vasin, Pavel},
  TITLE = {Blackcoin's proof-of-stake protocol v2},
  URL = {http://blackcoin.co/blackcoin-pos-protocol-v2-whitepaper.pdf},
  YEAR = {2014},
}

@ARTICLE{king2012ppcoin,
  AUTHOR = {King, Sunny and Nadal, Scott},
  JOURNALTITLE = {self-published paper, August},
  TITLE = {Ppcoin: Peer-to-peer crypto-currency with proof-of-stake},
  URL = {https://decred.org/research/king2012.pdf},
  VOLUME = {19},
  YEAR = {2012},
}

@INPROCEEDINGS{bentov2016pos,
  AUTHOR = {Iddo Bentov and Ariel Gabizon and Alex Mizrahi},
  BOOKTITLE = {International Conference on Financial Cryptography and Data Security},
  EDITOR = {Radu Sion},
  ORGANIZATION = {Springer},
  PAGES = {142--157},
  TITLE = {Cryptocurrencies without proof of work},
  YEAR = {2016},
}

@INPROCEEDINGS{selfishminingBTC,
  AUTHOR = {Ayelet Sapirshtein and Yonatan Sompolinsky and Aviv Zohar},
  BOOKTITLE = {International Conference on Financial Cryptography and Data Security},
  EDITOR = {Radu Sion},
  ORGANIZATION = {Springer},
  PAGES = {515--532},
  TITLE = {Optimal selfish mining strategies in bitcoin},
  YEAR = {2016},
}

@MISC{minslashing,
  AUTHOR = {Vitalik Buterin},
  DAY = {02},
  MONTH = {03},
  TITLE = {Minimal Slashing Conditions},
  URL = {https://medium.com/@VitalikButerin/minimal-slashing-conditions-20f0b500fc6c},
  YEAR = {2017},
}

@MISC{truebit,
  AUTHOR = {Jason Teustch and Christian Reitwießner},
  DAY = {07},
  MONTH = {03},
  TITLE = {A scalable verification solution for blockchains},
  URL = {https://truebit.io/},
  YEAR = {2017},
}

@ARTICLE{ostrom2002,
  AUTHOR = {Ostrom, Elinor},
  JOURNALTITLE = {unpublished paper},
  PAGES = {15},
  TITLE = {Type of good and collective action},
  YEAR = {2002},
}

@MISC{barder14,
  AUTHOR = {Alice Lépissier and Owen Barder},
  DAY = {08},
  MONTH = {09},
  TITLE = {A Global Carbon Tax or Cap-and-Trade? Part 1: The Economic Arguments},
  URL = {https://www.cgdev.org/blog/global-carbon-tax-or-cap-and-trade-part-1-economic-arguments},
  YEAR = {2014},
}

@MISC{braveICO,
  AUTHOR = {Jon Southurst},
  DAY = {31},
  MONTH = {05},
  TITLE = {BAT Token Sale Causes Hours of Ethereum Network Delays},
  URL = {http://www.bitsonline.com/bat-sale-ethereum-network-delays/},
  YEAR = {2017},
}

@REPORT{ibm2011,
  AUTHOR = {Richard F. Freitas and Joe Slember and Wayne Sawdon and Lawrence Chiu},
  DAY = {22},
  INSTITUTION = {IBM},
  MONTH = {07},
  TITLE = {GPFS Scans 10 Billion Files in 43 Minutes},
  TYPE = {techreport},
  URL = {https://domino.research.ibm.com/library/CyberDig.nsf/papers/4A50C2D66A1F90F7852578E3005A2034/$File/rj10484.pdf},
  YEAR = {2011},
}

@MISC{infura,
  AUTHOR = {Consensys},
  DAY = {01},
  MONTH = {06},
  TITLE = {INFURA},
  URL = {https://infura.io},
  YEAR = {2017},
}

@MISC{spectrumetcalfe,
  AUTHOR = {Bob Briscoe, Andrew Odlyzko, and Benjamin Tilly},
  DAY = {01},
  MONTH = {06},
  TITLE = {Metcalfe's Law is Wrong},
  URL = {http://spectrum.ieee.org/computing/networks/metcalfes-law-is-wrong},
  YEAR = {2006},
}

@MISC{env-econ,
  AUTHOR = {Tim Haab},
  DAY = {23},
  MONTH = {06},
  TITLE = {The long run elasticity of demand for gas},
  URL = {http://www.env-econ.net/2008/06/the-long-run-el.html},
  YEAR = {2008},
}

@INPROCEEDINGS{cornell-position,
  AUTHOR = {Kyle Croman and Christian Decker and Ittay Eyal and Adem Efe Gencer and Ari Juels},
  BOOKTITLE = {3rd Workshop on Bitcoin and Blockchain Research},
  EDITOR = {Sarah Meiklejohn and Jeremy Clark},
  ORGANIZATION = {International Financial Cryptography Association},
  TITLE = {On Scaling Decentralized Blockchains},
  URL = {http://fc16.ifca.ai/bitcoin/papers/CDE+16.pdf},
  YEAR = {2017},
}

@MISC{medium-codetract,
  AUTHOR = {CodeTract},
  DAY = {01},
  MONTH = {06},
  TITLE = {BAT ICO, USD 35 million in 24 seconds, gas and gasPrice},
  URL = {https://medium.com/@codetractio/bat-ico-usd-35-million-in-24-seconds-gas-and-gasprice-6cdde370a615},
  YEAR = {2017},
}

@MISC{vitalik-uncle-rate,
  AUTHOR = {Vitalik Buterin},
  DAY = {31},
  MONTH = {10},
  TITLE = {Uncle Rate and Transaction Fee Analysis},
  URL = {https://blog.ethereum.org/2016/10/31/uncle-rate-transaction-fee-analysis/},
  YEAR = {2016},
}

@MISC{vitalik-twitter1,
  AUTHOR = {Vitalik Buterin},
  DAY = {03},
  MONTH = {06},
  TITLE = {Tweet},
  URL = {https://twitter.com/VitalikButerin/status/871218258212290560},
  YEAR = {2017},
}

@MISC{reddit-rec-miners,
  AUTHOR = {Hudson Jameson},
  DAY = {31},
  MONTH = {05},
  TITLE = {Recommendations to miners to change gas limit and gas price settings},
  URL = {https://www.reddit.com/r/ethereum/comments/6ehp60/recommendations_to_miners_to_change_gas_limit_and/},
  YEAR = {2017},
}

@MISC{coindesk-btc-txn-fee,
  AUTHOR = {Danny Bradbury},
  DAY = {28},
  MONTH = {02},
  TITLE = {Bitcoin Transaction Fees To Be Slashed Tenfold},
  URL = {http://www.coindesk.com/bitcoin-transaction-fees-slashed-tenfold/},
  YEAR = {2014},
}

@MISC{vitalik-coord,
  AUTHOR = {Vitalik Buterin},
  DAY = {08},
  MONTH = {05},
  TITLE = {Engineering Security Through Coordination Problems},
  URL = {http://vitalik.ca/general/2017/05/08/coordination_problems.html},
  YEAR = {2017},
}

@MISC{etherchaingas,
  AUTHOR = {Etherchain},
  DAY = {01},
  MONTH = {May},
  TITLE = {Economic gas price estimation},
  URL = {https://etherchain.org/statistics/gasPrice},
  YEAR = {2017},
}

@MISC{40years,
  AUTHOR = {Karl Rupp},
  DAY = {25},
  MONTH = {06},
  TITLE = {40 Years of Microprocessor Trend Data},
  URL = {https://www.karlrupp.net/2015/06/40-years-of-microprocessor-trend-data/},
  YEAR = {2015},
}

@MISC{wiki:runaway,
  AUTHOR = {Wikipedia},
  NOTE = {[Online; accessed 5-May-2017]},
  TITLE = {Runaway climate change --- Wikipedia{,} The Free Encyclopedia},
  URL = {https://en.wikipedia.org/w/index.php?title=Runaway_climate_change&oldid=776345569},
  YEAR = {2017},
}

@MISC{wood2014ethereum,
  AUTHOR = {Gavin Wood},
  TITLE = {Ethereum: A Secure Decentralized Generalized Transaction Ledger},
  URL = {http://yellowpaper.io/},
  YEAR = {2014},
}

@ARTICLE{weitzman1974prices,
  AUTHOR = {Martin L Weitzman},
  JOURNALTITLE = {The review of economic studies},
  NUMBER = {4},
  PAGES = {477--491},
  TITLE = {Prices vs. quantities},
  VOLUME = {41},
  YEAR = {1974},
}

@MISC{bip:141,
  AUTHOR = {Eric Lombrozo, Johnson Lau, and Pieter Wuille},
  DAY = {21},
  MONTH = {12},
  TITLE = {BIP 141: Segregated Witness},
  URL = {https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki},
  YEAR = {2015},
}

@BOOK{knight1921risk,
  AUTHOR = {Knight, Frank H},
  PUBLISHER = {Courier Corporation},
  TITLE = {Risk, uncertainty and profit},
  YEAR = {1921},
}

@INPROCEEDINGS{fc17ai,
  AUTHOR = {McCorry, Patrick and Shahandashti, Siamak F. and Hao, Feng},
  BOOKTITLE = {Proceedings of Financial Cryptography and Data Security},
  EDITOR = {Rainer Böhme and Tatsuaki Okamoto},
  ORGANIZATION = {International Financial Cryptography Association},
  TITLE = {A Smart Contract for Boardroom Voting with Maximum Voter Privacy},
  URL = {http://fc17.ifca.ai/preproceedings/paper_80.pdf},
  YEAR = {2017},
}

@ARTICLE{vigna13fibonacci,
  AUTHOR = {Sebastiano Vigna},
  JOURNALTITLE = {CoRR},
  TITLE = {Fibonacci Binning},
  URL = {http://arxiv.org/abs/1312.3749},
  VOLUME = {abs/1312.3749},
  YEAR = {2013},
}

@MISC{wiki:ricochet,
  AUTHOR = {Wikipedia},
  NOTE = {[Online; accessed 28-February-2017]},
  TITLE = {Ricochet (software) --- Wikipedia{,} The Free Encyclopedia},
  URL = {https://en.wikipedia.org/w/index.php?title=Ricochet_(software)&oldid=755044411},
  YEAR = {2016},
}

@ARTICLE{darknet,
  AUTHOR = {Manlio De Domenico and Alex Arenas},
  DOI = {10.1103/PhysRevE.95.022313},
  ISSUE = {2},
  JOURNALTITLE = {Phys. Rev. E},
  MONTH = {Feb},
  PAGES = {022313},
  TITLE = {Modeling structure and resilience of the dark network},
  URL = {http://link.aps.org/doi/10.1103/PhysRevE.95.022313},
  VOLUME = {95},
  YEAR = {2017},
}

@ARTICLE{borgatti1998network,
  AUTHOR = {Borgatti, Stephen P and Jones, Candace and Everett, Martin G},
  JOURNALTITLE = {Connections},
  NUMBER = {2},
  PAGES = {27--36},
  TITLE = {Network measures of social capital},
  VOLUME = {21},
  YEAR = {1998},
}

@MISC{wiki:torchat,
  AUTHOR = {Wikipedia},
  NOTE = {[Online; accessed 28-February-2017]},
  TITLE = {TorChat --- Wikipedia{,} The Free Encyclopedia},
  URL = {https://en.wikipedia.org/w/index.php?title=TorChat&oldid=728783759},
  YEAR = {2016},
}

@MISC{wiki:tormessenger,
  AUTHOR = {Wikipedia},
  NOTE = {[Online; accessed 28-February-2017]},
  TITLE = {Tor (anonymity network) --- Wikipedia{,} The Free Encyclopedia},
  URL = {https://en.wikipedia.org/w/index.php?title=Tor_(anonymity_network)#Tor_Messenger&oldid=767770868},
  YEAR = {2017},
}

@REPORT{pagerank,
  ABSTRACT = {The importance of a Web page is an inherently subjective matter, which depends on the readers interests, knowledge and attitudes. But there is still much that can be said objectively about the relative importance of Web pages. This paper describes PageRank, a mathod for rating Web pages objectively and mechanically, effectively measuring the human interest and attention devoted to them. We compare PageRank to an idealized random Web surfer. We show how to efficiently compute PageRank for large numbers of pages. And, we show how to apply PageRank to search and to user navigation.},
  AUTHOR = {Lawrence Page and Sergey Brin and Rajeev Motwani and Terry Winograd},
  INSTITUTION = {Stanford InfoLab},
  MONTH = {November},
  NOTE = {Previous number = SIDL-WP-1999-0120},
  NUMBER = {1999-66},
  TITLE = {The PageRank Citation Ranking: Bringing Order to the Web.},
  TYPE = {Technical Report},
  URL = {http://ilpubs.stanford.edu:8090/422/},
  YEAR = {1999},
}

@BOOK{everton2012disrupting,
  AUTHOR = {Everton, Sean F},
  PUBLISHER = {Cambridge University Press},
  TITLE = {Disrupting dark networks},
  VOLUME = {34},
  YEAR = {2012},
}

@ARTICLE{broder2000graph,
  AUTHOR = {Andrei Broder and Ravi Kumar and Farzin Maghoul and Prabhakar Raghavan and Sridhar Rajagopalan and Raymie Stata and Andrew Tomkins and Janet Wiener},
  JOURNALTITLE = {Computer networks},
  NUMBER = {1},
  PAGES = {309--320},
  TITLE = {Graph structure in the web},
  VOLUME = {33},
  YEAR = {2000},
}

@ARTICLE{rfc7686,
  AUTHOR = {Appelbaum, Jacob and Muffet, Alex},
  ISSN = {2070-1721},
  JOURNALTITLE = {Internet Engineering Task Force RFC},
  MONTH = {Oct},
  TITLE = {The ``.onion'' Special-Use Domain Name},
  URL = {https://tools.ietf.org/html/rfc7686},
  VOLUME = {7686},
  YEAR = {2015},
}

@ARTICLE{clauset2009power,
  AUTHOR = {Clauset, Aaron and Shalizi, Cosma Rohilla and Newman, Mark EJ},
  JOURNALTITLE = {SIAM review},
  NUMBER = {4},
  PAGES = {661--703},
  TITLE = {Power-law distributions in empirical data},
  VOLUME = {51},
  YEAR = {2009},
}

@ARTICLE{meusel2015graph,
  AUTHOR = {Meusel, Robert and Vigna, Sebastiano and Lehmberg, Oliver and Bizer, Christian},
  JOURNALTITLE = {The Journal of Web Science},
  NUMBER = {1},
  TITLE = {The Graph Structure in the Web--Analyzed on Different Aggregation Levels},
  VOLUME = {1},
  YEAR = {2015},
}

@ARTICLE{Serrano2007,
  AUTHOR = {Serrano, M. Ángeles and Maguitman, Ana and Boguñá, Marián and Fortunato, Santo and Vespignani, Alessandro},
  DOI = {10.1145/1255438.1255442},
  ISSN = {1559-1131},
  JOURNALTITLE = {ACM Trans. Web},
  KEYWORDS = {Web graph structure, Web measurement, crawler biases, statistical analysis},
  MONTH = {08},
  NUMBER = {2},
  TITLE = {Decoding the Structure of the WWW: A Comparative Analysis of Web Crawls},
  URL = {http://doi.acm.org/10.1145/1255438.1255442},
  VOLUME = {1},
  YEAR = {2007},
}

@ARTICLE{bollobas2004robustness,
  AUTHOR = {Bollobás, Béla and Riordan, Oliver},
  JOURNALTITLE = {Internet Mathematics},
  NUMBER = {1},
  PAGES = {1--35},
  TITLE = {Robustness and vulnerability of scale-free random graphs},
  VOLUME = {1},
  YEAR = {2004},
}

@ARTICLE{barabasi1999emergence,
  AUTHOR = {Barabási, Albert-László and Albert, Réka},
  JOURNALTITLE = {science},
  NUMBER = {5439},
  PAGES = {509--512},
  TITLE = {Emergence of scaling in random networks},
  VOLUME = {286},
  YEAR = {1999},
}

@ARTICLE{willinger2013internet,
  AUTHOR = {Willinger, Walter and Roughan, Matthew},
  JOURNALTITLE = {ACM SIGCOMM eBook: Recent Advances in Networking},
  TITLE = {Internet topology research redux},
  YEAR = {2013},
}

@ARTICLE{willinger2009mathematics,
  AUTHOR = {Willinger, Walter and Alderson, David and Doyle, John C},
  JOURNALTITLE = {Notices of the AMS},
  NUMBER = {5},
  PAGES = {586--599},
  TITLE = {Mathematics and the internet: A source of enormous confusion and great potential},
  VOLUME = {56},
  YEAR = {2009},
}

@ARTICLE{pansiot1998routes,
  AUTHOR = {Jean-Jacques Pansiot and Dominique Grad},
  JOURNALTITLE = {ACM SIGCOMM Computer Communication Review},
  NUMBER = {1},
  PAGES = {41--50},
  TITLE = {On routes and multicast trees in the Internet},
  VOLUME = {28},
  YEAR = {1998},
}

@THESIS{jovanovic2001modeling,
  AUTHOR = {Jovanovic, Mihajlo A},
  INSTITUTION = {University of Cincinnati},
  TITLE = {Modeling large-scale peer-to-peer networks and a case study of Gnutella},
  TYPE = {mathesis},
  YEAR = {2001},
}

@ARTICLE{barabasi2000scale,
  AUTHOR = {Barabási, Albert-László and Albert, Réka and Jeong, Hawoong},
  JOURNALTITLE = {Physica A: Statistical Mechanics and its Applications},
  NUMBER = {1},
  PAGES = {69--77},
  TITLE = {Scale-free characteristics of random networks: the topology of the world-wide web},
  VOLUME = {281},
  YEAR = {2000},
}

@ARTICLE{siganos2003power,
  AUTHOR = {Siganos, Georgos and Faloutsos, Michalis and Faloutsos, Petros and Faloutsos, Christos},
  JOURNALTITLE = {IEEE/ACM Transactions on Networking (TON)},
  NUMBER = {4},
  PAGES = {514--524},
  TITLE = {Power laws and the AS-level internet topology},
  VOLUME = {11},
  YEAR = {2003},
}

@ARTICLE{albert2001physics,
  AUTHOR = {Albert-László Barabási, July},
  JOURNALTITLE = {Physics Web http://www.physicsweb.org/article/world/14/7/09},
  TITLE = {The physics of the Web},
  YEAR = {2001},
}

@ARTICLE{cohen2001breakdown,
  AUTHOR = {Cohen, Reuven and Erez, Keren and Ben-Avraham, Daniel and Havlin, Shlomo},
  JOURNALTITLE = {Physical review letters},
  NUMBER = {16},
  PAGES = {3682},
  TITLE = {Breakdown of the Internet under intentional attack},
  VOLUME = {86},
  YEAR = {2001},
}

@ARTICLE{albert2000error,
  AUTHOR = {Albert, Réka and Jeong, Hawoong and Barabási, Albert-László},
  JOURNALTITLE = {Nature},
  NUMBER = {6794},
  PAGES = {378--382},
  TITLE = {Error and attack tolerance of complex networks},
  VOLUME = {406},
  YEAR = {2000},
}

@ARTICLE{adamic2000power,
  AUTHOR = {Adamic, Lada A and Huberman, Bernardo A},
  JOURNALTITLE = {Science},
  NUMBER = {5461},
  PAGES = {2115--2115},
  TITLE = {Power-law distribution of the world wide web},
  VOLUME = {287},
  YEAR = {2000},
}

@MISC{tormetrics,
  AUTHOR = {The Tor Project},
  MONTH = {January},
  TITLE = {TorMetrics --- Unique .onion addresses},
  URL = {https://metrics.torproject.org/hidserv-dir-onions-seen.html},
  YEAR = {2017},
}