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I am using the following multiline equation. The last line of the equation unfortunately is indented and goes across the two columns. How can contain the last line in terms of its indentation?
\documentclass[journal]{IEEEtran}
\usepackage{amsmath}
\usepackage{adjustbox}% http://ctan.org/pkg ...

I would like to put a brace on top of a multiline equation. For instance in the following equation I want a brace on top of "k+l+m" which are broken over two lines. How can I do this?

I tried \overbrace{}^{\text{}} but it doesn't like multi lines (i.e. \\ inside \overbrace{}).

\begin{equation ...