Complex sentence: There is some confusion over both Wilkins' date of birth and death; various sources quote 1921 or 1922 as his year of birth, and some cite 1981 for his death.
Split into simpler sentences: There is some confusion over both the precise date of birth, and death, for Wilkins. Various sources quote 1921 or 1922 as his year of birth, and some cite 1981 for his death.