ABSTRACT
The authors' journey in the development of the field of differential subordinations began innocently enough while working in the field of univalent functions . It began in a 1974 article [ 202 ], coauthored with Maxwell 0 . Reade, which dealt with properties of Bazilevic functions. In
that article the following lemma was proved: if a is real and p is analytic in the unit disk, then
This result enables us to detect properties of the range of a function from the range of a combination of the derivatives of the function. There were not
many known differential implications of this type in the theory of analytic functions.
