▁Sub sequently ▁he ▁went ▁to ▁England ▁to ▁study ▁with ▁Bernard ▁Lewis ▁and ▁Paul ▁W itte k ▁at ▁the ▁School ▁of ▁Oriental ▁and ▁African ▁Studies , ▁University ▁of ▁London ▁and ▁with ▁Professor ▁H . ▁A . ▁R . ▁Gib b ▁at ▁Oxford ▁University . ▁ ▁Following ▁this , ▁he ▁went ▁to ▁Egypt ▁to ▁study ▁with ▁Sh af i q ▁G hor bal ▁and ▁Ad olph ▁Gro h mann ▁at ▁the ▁University ▁of ▁C airo ▁and ▁Sh a ikh ▁Say y id ▁at ▁the ▁Az har ▁University , ▁also ▁doing ▁research ▁in ▁the ▁Ott oman ▁arch ives ▁of ▁Egypt ▁at ▁the ▁Cit adel ▁in ▁C airo ▁for ▁his ▁Pr inc eton ▁Ph . D . ▁dis sert ation ▁concerning ▁Ott oman ▁rule ▁in ▁Egypt . ▁Before ▁leaving ▁Egypt , ▁he ▁had ▁a ▁personal ▁interview ▁with ▁President ▁Gam al ▁Abd ▁al - N asser , ▁who ▁arranged ▁for ▁him ▁to ▁take ▁micro fil ms ▁of ▁Ott oman ▁documents ▁out ▁of ▁the ▁country . ▁ ▁Main ▁research ▁In ▁ 1 9 5 6 - 7 ▁he ▁studied ▁at ▁the ▁University ▁of ▁Ist an bul ▁with ▁Prof ess ors ▁O mer ▁L ut fi ▁B ark an , ▁M uk rimin ▁Hal il ▁Y in anc , ▁Hal il ▁Sah illi og lu , ▁and ▁Z ek i ▁Vel idi ▁T og an , ▁also ▁comple ting ▁research ▁on ▁his ▁dis sert ation ▁in ▁the ▁Ott oman ▁arch ives ▁of ▁Ist an bul , ▁where ▁he ▁was ▁helped ▁by ▁a ▁number ▁of ▁staff ▁members , ▁including ▁Z i