Memoirs of the American Mathematical Society, ISSN 0065-9266 ; Number 438
Print version: Lopez, Angelo Felice, 1958- Noether-Lefschetz theory and the Picard group of projective surfaces. Providence, Rhode Island : American Mathematical Society, c1991 ix, 100 pages Memoirs of the American Mathematical Society ; Number 438. ISBN 9780821825006
"January 1991, Volume 89, Number 438 (first of 3 numbers)."