# How to use feynmf (feynmp)? [duplicate]

I would like to draw a tadpole diagram with a cross in a circle as the picture in the parenthesis but the double line is not necessary.

I write the codes as below:

\begin{fmffile}{tadpole}
\begin{fmfgraph*}(50,25)
\fmfright{o1}
\fmfpoly{cross,pull=?}{v1}
\fmf{plain}{v1,o1}
\fmfdot{v1}
\end{fmfgraph*}
\end{fmffile}


What I worry about is \fmfpoly{cross,pull=?}{v1}. I think this should be wrong, but I really don't know how to present a cross in a circle.

I hope somebody can help me. Thank you very much.

## marked as duplicate by Stefan Pinnow, Community♦Oct 27 '16 at 13:42

• \otimes? (in math mode) – Henri Menke Oct 27 '16 at 9:14
• @HenriMenke I am afraid this would not work since I need the external line to be connected with the \otimes symbol. And actually I hope to draw a dot at the point of junction. – Wein Eld Oct 27 '16 at 9:17
• Possibe duplicate of this question? – campa Oct 27 '16 at 9:34
• Welcome to TeX.SX! Can you please expand the code snippets that you have posted to a full minimal working example. It is much easier to help you you if we can start with some compilable code that illustrates your problem. A MWE should compile and be as small as possible to demonstrate your problem. – Andrew Oct 27 '16 at 13:36

\documentclass{article}
$\delta J(\otimes\mkern-7mu\cdot\!\!\mbox{---}) =0$