This is a theory section
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I might want to describe some equations:
.. math::
\int_0^\infty e^{-x^2} dx=\frac{\sqrt{\pi}}{2}
And refer to a paper [author2015]_.
.. [author2015] first a., second a., cheese b. (2015). The title of their
paper. Journal of papers, *15*: 1023-1049.