Subordination and superordination for multivalent functions defined by   linear operators
  In this paper, certain linear operators defined on $p$-valent analytic functions have been unified and for them some subordination and superordination results as well as the corresponding sandwich type results are obtained. A related integral transform is discussed and sufficient conditions for functions in different classes have been obtained. 
S. Sivaprasad Kumar, Virendra Kumar, V. Ravichandran
math.CV