Integer solutions of some Diophantine equations via Fibonacci and Lucas numbers. Demirtürk, Bahar; Keskin, Refik — 2009 Journal of Integer Sequences [electronic only]
On suborbital graphs for the normalizer of Γ 0 ( N ) . Keskin, Refik; Demirtürk, Bahar — 2009 The Electronic Journal of Combinatorics [electronic only]