Maybe this will help: http://tex.stackexchange.com/questions/173938/how-to-create-this-arrow-with-letters-above-and-below?rq=1
– Romain PicotJan 04 '16 at 07:45
1 Answers1
1
\documentclass{article}
\usepackage{amssymb}
\begin{document}
\[ u \mathrel{\mathop{\rightsquigarrow}^{p}} v \]
\end{document}