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Its from an old plant taxonomy handout from when I was in college. Here's photos, 3 pages.
I'm pretty sure it comes from this book, An Integrated System of Classification of Flowering Plants by Arthur Conquist, 1981 I can't find an e-book version.
This taxonomy is based on the Cronquist system, now dated, as most contemporary botanists use the Angiosperm Phylogeny Group classification, developed in 1998.