The Cronquist system has been very popular, and there have been many versions of the system published. In some of these Cronquist-based systems the name Magnoliopsida (at the rank of class) refers to the flowering plants (angiosperms).
In the APG and APG II systems, botanical names are used only at the rank of order and below. Above the rank of order, these systems use their own names, such as angiosperms, eudicots, monocots, rosids, etc. These names refer to clades (unranked). The class Magnoliopsida is not defined. The idea that dicotyledons are a taxonomic unit and require a formal name is rejected by the APG: the dicots are considered to be paraphyletic.
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