os can ini ▁Memorial ▁Archives , ▁a ▁collection ▁of ▁micro film ▁copies ▁of ▁significant ▁music ▁manuscript s ▁in ▁other ▁libraries . ▁From ▁ 1 9 8 7 ▁to ▁ 1 9 9 7 ▁she ▁was ▁the ▁head ▁of ▁the ▁Cir cul ating ▁Col lections ▁of ▁the ▁New ▁York ▁Public ▁Library ▁for ▁the ▁Perform ing ▁Arts . ▁ ▁She ▁was ▁chief ▁of ▁the ▁Music ▁Division ▁from ▁ 1 9 9 7 ▁to ▁ 2 0 0 1 , ▁the ▁latter ▁two ▁years ▁concurrent ▁with ▁being ▁the ▁acting ▁director ▁of ▁the ▁New ▁York ▁Public ▁Library ▁for ▁the ▁Perform ing ▁Arts ▁from ▁ 1 9 9 9 ▁to ▁ 2 0 0 1 . ▁ ▁She ▁retired ▁in ▁ 2 0 0 1 .< ref ▁name = ob it >" S us an ▁Th iemann ▁( Su ki ) ▁Sommer ," ▁New ▁York ▁Times ▁( Mar . ▁ 9 , ▁ 2 0 0 8 ). </ ref > ▁ ▁She ▁joined ▁the ▁fac ulty ▁of ▁Columbia ▁University ' s ▁School ▁of ▁Library ▁Service ▁in ▁ 1 9 6 9 ▁where ▁she ▁taught ▁music ▁li br ari ans hip ▁and ▁performing ▁arts ▁bibli ography ▁until ▁the ▁school ' s ▁dem ise ▁in ▁ 1 9 9 2 , ▁ear ning ▁a ▁highly ▁regarded ▁reputation . ▁ ▁Begin ning ▁in ▁ 1 9 6 0 , ▁Sommer ▁contributed ▁reviews ▁to ▁High ▁F idel ity / Mus ical ▁America . ▁ ▁For ▁a ▁while ▁she ▁was ▁editor ▁of ▁Current ▁Music ology , ▁and ▁contributed ▁to ▁Musical ▁Qu arter