▁he ▁joined ▁as ▁the ▁li br arian ▁of ▁the ▁Central ▁Library ▁of ▁the ▁university ▁in ▁June ▁ 1 9 5 6 , ▁a ▁position ▁he ▁held ▁until ▁his ▁ret irement ▁in ▁ 1 9 7 2 . ▁Khan ▁introduced ▁a ▁di pl oma ▁course ▁for ▁Library ▁Science ▁and , ▁along ▁with ▁A hm ad ▁H oss ain , ▁founded ▁the ▁Library ▁Association ▁of ▁East ▁Pakistan . ▁When ▁the ▁Department ▁of ▁Library ▁Science ▁was ▁established ▁in ▁ 1 9 5 9 , ▁he ▁was ▁appointed ▁the ▁head ▁of ▁the ▁department . ▁In ▁his ▁ 1 9 ▁years ▁of ▁service ▁to ▁the ▁Library , ▁he ▁introduced ▁the ▁De we y ▁Dec imal ▁System ▁of ▁library ▁classification ▁and ▁o vers aw ▁its ▁implementation . ▁He ▁faced ▁job - related ▁financial ▁troubles ▁when ▁he ▁retired . ▁ ▁K H an ▁was ▁the ▁vice - pres ident ▁of ▁the ▁Pakistan ▁Library ▁Association ▁( 1 9 5 7 , ▁ 1 9 5 8 , ▁and ▁ 1 9 6 8 ) ▁and ▁the ▁president ▁for ▁several ▁ten ures . ▁He ▁was ▁the ▁General ▁Secretary ▁of ▁ ▁from ▁ 1 9 6 2 ▁to ▁ 1 9 6 5 . ▁He ▁was ▁a ▁vice - pres ident ▁of ▁Asian ▁Federation ▁of ▁Library ▁Association ▁from ▁ 1 9 5 7 ▁to ▁ 1 9 6 0 . ▁ ▁Khan ▁wrote ▁a ▁number ▁of ▁books , ▁as ▁well ▁as ▁columns ▁for ▁Hol iday ▁and ▁The ▁Bang l adesh ▁Ob server . ▁He ▁published ▁a ▁news ▁bullet in ▁for ▁the ▁University ▁