_:b665101452 . _:b665101452 . _:b665101452 "ISBN:978-0471984931" . _:b665101452 . _:b665101452 "ISBN:0123195837" . _:b665101452 . _:b665101452 . _:b665101452 . _:b665101452 "Structural homology that involves complex structures from which only a fraction of the elements that can be isolated are separately homologous." .