1. Khabibullin B.N. Polnota sistem tselykh funktsii v prostranstvakh golomorfnykh funktsii, Matem. zametki 66 (4), 603–616 (1999
2. Khabibullin B.N. Excess of systems of exponentials in a domain, and directional convexity deficiency of a curve, St. Petersburg Math. J. 13 (6), 1047–1080 (2002).
3. Khabibullin B.N. Stability of Completeness for Systems of Exponentials on Compact Convex Sets in BbbC , Math. Notes 72 (4), 542–550 (2002).
4. Khabibullin B.N. Polnota sistem eksponent i mnozhestva edinstvennosti. Monografiya-obzor, 4-e izd., dop. (Redaktsionno-izdatel'skii tsentr BashGU, g. Ufa, 2012).
5. Kheifits A.I. Analiticheskie svoistva funktsii, vypuklykh otnositel'no reshenii lineinykh differentsial'nykh uravnenii vtorogo poryadka, Differents. uravneniya 17 (6), 1025–1034 (1981).