Abstract
The authors introduce a two-parameter function
G
(
p
,
λ
;
z
)
which is shown to play an important rôle in a unified presentation of many interesting subclasses of analytic and
p
-valent functions in the open unit disk
U
. Making use of the familiar principle of differential subordination, several properties and relationships involving the function
G
(
p
,
λ
;
z
)
are derived. Some sufficient conditions for
p
-valent starlikeness are also obtained.