549,493 NEW New frontiers in ophthalmology : Proceedings of the XXVI International Congress of Ophthalmology held in Singapore, 18-24 March 1990 /ed. board, chairman Khoo Chong Yew; members Ang Beng Chong [et al.]. - Amsterdam [etc.] : Excerpta Medica, 1991. - XCVI, 1218 s. : il., wvkr. ; 25 cm ISBN 0-444-81144-3