# Latex stops referencing theorem environment

I'm resuming a project after some weeks.

Now, when I reference some theorem, the result are that bored question marks (??). For theorems that already exists, refence to that works well, but referencing other theorems doesn't.

It's weird. Before all was fine.

For example:

\begin{def:conv_method_1}

...

\end{def:conv_method_1}

...

Theorem~\ref{def:conv_method_1}


and the result is

Theorem ??


Any trick?

## migrated from stackoverflow.comSep 3 '14 at 12:02

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• What packages are you using? Should your theorem definition say \begin{theorem}\label{def:conv_method_1} instead of \begin{def:conv_method_1}? – John Palmieri Jul 18 '14 at 20:43
• @JohnPalmieri I suggest you post that as an answer in its own right so it can be accepted. – swref Jul 18 '14 at 21:10

I think your theorem definition should say \begin{theorem}\label{def:conv_method_1} ... instead of \begin{def:conv_method_1} ....