“…Recently, in their pioneering work on the subject of bi-univalent functions, Srivastava et al [23] actually revived the study of the coefficient problems involving bi-univalent functions. Various subclasses of the bi-univalent function class Σ were introduced and non-sharp estimates on the first two coefficients |a 2 | and |a 3 | in the Taylor-Maclaurin series expansion (1) were found in several recent investigations (see, for example, [1,2,3,4,5,7,11,12,13,14,15,18,19,21,22,24,25] and references therein). The afore-cited papers on the subject were actually motivated by the pioneering work of Srivastava et al [23].…”