(everyone has to read this)
(mandatory if you choose this as your expertise topic)
Bizer, Christian, et al. “DBpedia-A crystallization point for the Web of Data.” Web Semantics: science, services and agents on the world wide web 7.3 (2009): 154-165.
Mahdisoltani, Farzaneh, Joanna Biega, and Fabian M. Suchanek. “Yago3: A knowledge base from multilingual wikipedias.” CIDR. 2013. https://suchanek.name/work/publications/cidr2015.pdf
Matuszek, Cynthia, et al. “An Introduction to the Syntax and Content of Cyc.” AAAI Spring Symposium: Formalizing and Compiling Background Knowledge and Its Applications to Knowledge Representation and Question Answering. 2006. https://www.researchgate.net/profile/Michael_Witbrock/publication/221250660_An_Introduction_to_the_Syntax_and_Content_of_Cyc/links/0c960537f65a4b25af000000.pdf
Bollacker, Kurt, et al. “Freebase: a collaboratively created graph database for structuring human knowledge.” Proceedings of the 2008 ACM SIGMOD international conference on Management of data. AcM, 2008. http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.538.7139&rep=rep1&type=pdf