I used the following reference books in 2014.
Not sure whether they are still applicable,
https://www.academia.edu/1593259/GRE_Computer_Science_Test_-_Practice_Book
https://books.google.lk/books/about/Preparing_for_Graduate_School_Examinatio.html?id=hc2CLUT73H0C&redir_esc=y
I should...