circulant matrices. invertible matrices. binary matrices with a prescribed number of ones. QC-LDPC McEliece cryptosystemFabšič, Tomáš, 1986- On generating invertible circulant binary matrices with a prescribed number of ones / aut. Tomáš Fabšič, Otokar Grošek, Karol Nemoga, Pavol Zajac. -- 2-s2.0-85041074817. -- 000428746900011. Grošek, Otokar, 1950-. Nemoga, Karol, 1953-. Zajac, Pavol, 1980- In: Cryptography and Communications. -- ISSN 1936-2447. -- Vol. 10, Iss. 1 (2018), s. 159-175.