Close-to-convexity and starlikeness of analytic functions
  For functions $f(z)=z^p+a_{n+1}z^{p+1}+...$ defined on the open unit disk, the condition $\Re (f'(z)/z^{p-1})>0$ is sufficient for close-to-convexity of $f$. By making use of this result, several sufficient conditions for close-to-convexity are investigated and relevant connections with previously known results are indicated. 
Lee See Keong, V. Ravichandran, Shamani Supramaniam
math.CV