@misc{cryptoeprint:2010:129, author = {N. Rajesh Pillai, S. S. Bedi, Sanjay Kumar, Roopika Chaudhary}, title = {Relation for Algebraic Attack on E0 combiner}, howpublished = {Cryptology ePrint Archive, Report 2010/129}, year = {2010}, note = {\url{https://ia.cr/2010/129}}, }You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.