PurbiantoroW.; UtomoN. B. P.; SudrajatO. A. THE ADDITION OF Ulva reticulata AS A STIMULANT INTO ARTIFICIAL FEED ON THE GONAD CONDITION OF THE COLLECTOR SEA URCHIN (Tripneustes gratilla LINNAEUS 1758). Jurnal Ilmu dan Teknologi Kelautan Tropis, v. 6, n. 1, 6 Nov. 2014.