[OS X TeX] Problem with refs to label in algorithmic

[Christopher Brewster]

I am using the 'algorithm' and 'algorithmic' styles to lay out an  
algorithm.
Using \ref{} to a label inside them produces an error:
"Latex Error: ./Chapters/chap10.tex:187 Undefined control sequence."

*However*, the references are correctly typeset.
Any suggestions?

Thanks,
Christopher


Example usage is this:
------
\begin{algorithm}[t]
	\caption{The Abraxas Algorithm}\label{al:abraxas}
	\begin{algorithmic}[1]
		\Procedure{Abraxas}{$C_i, P_i, T_i$}
....
		\State Increment iteration index:  $\{C_i, P_i, T_i| i = i + 1\}$
		\Until{\textbf{StoppingCriterion}}
		\EndProcedure
	\end{algorithmic}	
\end{algorithm}

We can describe the procedure presented in Algorithm \ref{al:abraxas}  
as follows: .....



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