Sentence:  In all his miscalculations , Stravinsky made the fatal historical blunder of presuming that he could transform other composers ' inspirations - representing many peoples , time periods and styles - into his <WSD>own</WSD> music by warping the harmony , melody , or form , to verify his own experiments . 
Meaning of the word marked with <WSD> tags:  belonging to or on behalf of a specified person (especially yourself); preceded by a possessive