The links below lead to official government websites or to the sources from the Instituto de Investigaciones Jurídicas, which is part of Universidad Nacional Autónoma de Mèxico (IIJ-UNAM), and considered the preeminent legal research center in Mexico. The federal government PDFs are kept current and are consider authoritative and official.
The library's Mexican law collection is downstairs in the foreign law section. It is organized under call number KGF. We do not keep current primary sources in print as they are available for free online. However, for historical research purposes, we have editions of many of the primary law sources.