Complex sentence: One of his Ph.D. students, Ilijas Farah, won the 1997 Sacks Prize for his Ph.D. The Ph.D. was received on June, 1997, at the University of Toronto.
Split into simpler sentences: One of his PhD students, Ilijas Farah, won the 1997 Sacks Prize for his PhD. The PhD was received on June, 1997, at the University of Toronto.