Many researchers create software as a critical part of their research. Whether it is data cleaning, processing, modeling, or visualizing, these software resources need to be integrated into the corpus of research objects. They also need to be described and referenced so that other members of the scholarly community can find them.
Software citation is an on-going interest of mine. I have several blogs and papers that describe my progress:
Citations for HDF Data and Software - An exploration of how HDF software is currently cited in DataCite metadata from many disciplines.