# The Blockchain Oracle Problem in Decentralized Finance--A Multivocal Approach
## Appendix A
### Bluzzle DeFi Oracle
(2021) Kaleem, M.; Shi, W. Demystifying Pythia: A Survey of ChainLink Oracles Usage on Ethereum. _arXiv_**2021**, arXiv:2101.06781. * Robert (2021) Robert, R. What Do You Look for in a Classic Literature Review? Available online: [[https://classic-literature.yoexpert.com/](https://classic-literature.yoexpert.com/)]([https://classic-literature.yoexpert.com/](https://classic-literature.yoexpert.com/)) classic-literature-general/what-do-you-look-for-in-a-classic-literature-revie-30604.html (accessed on 12 January 2021). * Sutherland (2004) Sutherland, S.E. An introduction to systematic reviews. _J. Evid. Based. Dent. Pract._**2004**, \(4\), 47-51. [CrossRef]
* Alhamary et al. (2019) Alhamary, A.; Alhasri, S.; Almasri, M.; Gillani, S. Blockchain-Based Applications in Education: A Systematic Review. _Appl. Sci._**2019**, \(9\), 2400. [CrossRef]
* Ahmed (2019) Ahmed, U. The Importance of Cross-Border Regulatory Cooperation in an Era of Digital Trade. _World Trade Rev._**2019**, _18_, 599-5120. [CrossRef]
* Kursawe and Wendy (2020) Kursawe, K. Wendy, the Good Little Fairness Widget: Achieving Order Fairness for Blockchains. In _Proceedings of the 2 nd ACM Conference on Advances in Financial Technologies_; Association for Computing Machinery: New York, NY, USA, 2020; pp. 25-36. [CrossRef]
* Elghaish et al. (2020) Elghaish, F.; Abrishami, S.; Hosseini, M.R. Integrated project delivery with blockchain: An automated financial system. _Autom. Constr._**2020**, _114_, 103182. [CrossRef]
* Fedorova and Skobleva (2020) Fedorova, E.P. ; Skobleva, E.I. Application of blockchain technology in higher education. _Eur. J. Contemp. Educ._**2020**, \(9\), 552-571. [CrossRef]
* Ogawa and Malen (2016) Ogawa, R.T.; Malen, B. Towards Rigor in Reviews of Multivocal Literatures: Applying the Exploratory Case Study Method. _Rev. Ed. Rad._**2016**, _61_, 265-286. [CrossRef]
* Schopfel and Farace (2010) Schopfel, J.; Farace, D.J. Grey Literature. _Encycl. Libr. Inf. Sci._**2010**, \(3\), 2029-2039. * Eskandari et al. (2021) Eskandari, S.; Salehi, M.; Gu, W.C.; Clark, J. _SoK: Onacles from the Ground Truth to Market Manipulation_; Association for Computing Machinery: New York, NY, USA, 2021; Volume 1. * Kitchenham and Charters (2007) Kitchenham, B.; Charters, S. Guidelines for Performing Systematic Literature Reviews in Software Engineering. 2007, Volume 1. Available online: [[https://www.elsevier.com/_data/promis_misc/525444](https://www.elsevier.com/_data/promis_misc/525444) systematicreviewsguide.pdf]([https://www.elsevier.com/_data/promis_misc/525444](https://www.elsevier.com/_data/promis_misc/525444) systematicreviewsguide.pdf) (accessed on 2 April 2021). * Wang et al. (2019) Wang, H.; Wang, Y.; Cao, Z.; Li, Z.; Xiong, G. An overview of blockchain security analysis. _Commun. Comput. Inf. Sci._**2019**, _970_, 55-72. [CrossRef]
* Bartoletti et al. (2020) Bartoletti, M.; Chiang, J.H. ; Lluch-Lafuente, A. SoK: Lending Pools in Decentralized Finance. _arXiv_**2020**, arXiv:2012.13230. * Harwick and Caton [2020] Harwick, C.; Caton, J. What's holding back blockchain finance? On the possibility of decentralized autonomous finance. _Q. Rev. Econ. Financ._**2020**. [CrossRef]
* Boado [2021] Boado, E. AAVE Protocol Whitepaper. Available online: [[https://github.com/aave/protocol-v2/blob/master/aave-v2](https://github.com/aave/protocol-v2/blob/master/aave-v2)]([https://github.com/aave/protocol-v2/blob/master/aave-v2](https://github.com/aave/protocol-v2/blob/master/aave-v2)) -whitepaper.pdf (accessed on 2 April 2021). * Leshner and Hayes [2018] Leshner, R.; Hayes, G. Compound: The Money Market Protocol. White Paper. 2018. Available online: [[https://www.digitalcoindata.com/whitepapers/compound-whitepaper.pdf](https://www.digitalcoindata.com/whitepapers/compound-whitepaper.pdf)]([https://www.digitalcoindata.com/whitepapers/compound-whitepaper.pdf](https://www.digitalcoindata.com/whitepapers/compound-whitepaper.pdf)) (accessed on 2 April 2021). * Juliano [2018] Juliano, A. \(\text{{\rm{}}}\)dYdX: A Standard for Decentralized Margin Trading and Derivatives. 2018.