Pinus L. subgenus Strobus Lemmon, Pinaceae, The high altitude white pines of Mexico and the adjacent SW USA, Michael Franks, 2008 PDF
The newly described white pine from northeast Mexico Pinus stylesii Frankis ex Businský is compared with other related pines, including P. flexilis James, P. reflexa (Engelm.) Engelm., P. strobiformis Engelm., P. veitchii Roezl, and P. ayacahuite Ehrenberg ex Sclechtendal. The new combination Pinus strobiformis subsp. veitchii (Roezl) Frankis is made, transferring this taxon from P. ayacahuite under which it has traditionally been treated as P. ayacahuite var. veitchii (Roezl) Shaw.