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who sang it's so hard to say goodbye to yesterday
It's So Hard to Say Goodbye to Yesterday was recorded in an a cappella rendition by contemporary R&B Motown group Boyz II Men
who sang it's so hard to say goodbye to yesterday originally
Written for the 1975 film Cooley High, It's So Hard to Say Goodbye to Yesterday is performed by Motown artist G.C. Cameron.

Question: who wrote the song
Self-contained rewrite: who wrote it's so hard to say goodbye to yesterday