The effects of ursodeoxycholic acid alone and ursodeoxycholic acid plus low-dose acetylsalicylic acid on radiolucent gallstones - TUNCER, İlyas; HARMAN, Mustafa; MERCAN, Rıdvan; ÖZTÜRK, Mustafa; ARSLAN, İsmail; MERAL, Cezmi; Türkdoğan, M. Kürşat (Turkish Journal of Gastroenterology, 2003)