Angiosperm Phylogeny Group

The Angiosperm Phylogeny Group (APG) is an informal international group of systematic botanists who collaborate to establish a consensus on the taxonomy of flowering plants (angiosperms) that reflects new knowledge about plant relationships discovered through phylogenetic studies. As of 2016, four incremental versions of a classification system have resulted from this collaboration, published in 1998, 2003, 2009 and 2016.

Source: Wikipedia — Angiosperm Phylogeny Group (CC BY-SA 4.0)