APA aipamena

Beukers, F. (1979). The generalised Ramanujan-Nagell equation. s.n..

Chicago Style aipamena

Beukers, Frits. The Generalised Ramanujan-Nagell Equation. [S.l.: s.n., 1979.

MLA aipamena

Beukers, Frits. The Generalised Ramanujan-Nagell Equation. s.n., 1979.