In file \file{exercises/references/references.tex}, replace \enquote{in the 
figure} and \enquote{the following source code listing} with suited references. 
Use the command \code{latex}{\textbackslash cref}. Do not forget to first 
introduce 
labels for the elements that you want to reference. To do so, first of all, 
wrap the source code listing in a \code{latex}{listing} environment. Also 
insert a caption for the source code listing. 
Make sure to use suitable prefixes before the labels.

\exercisematerial{exercises/references/references}
