Advances in pituitary adenoma research : proceedings of the Fourth European Workshop on Pituitary Adenomas, 13th-16th September 1987, Zurich, Switzerland - Landolt, Alex M. 1935-; Heitz, P. U.; Zapf, J.; Girard, J.; Pozo, Emilio del 1932- (Advances in the biosciences ;, 1988)