"The ABC model was popularized in a review in Nature published later in 1991 by the senior author and Enrico Coen, whose group had been making parallel new findings of similar homeotic mutants in snapdragon. [...] The ABC model is still widely used as a framework for understanding floral development today."
January 1, 1970
https://en.wikiquote.org/wiki/ABC_model_of_flower_development