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Ana Gabriela Zacarías-Correa, Emmanuel Pérez, Marie-Stéphanie Samain: Penstemon dugesii (Plantaginaceae), a new species from Guanajuato, Mexico. In: Phytotaxa, Volume 447, Issue 3, Juni 2020. doi:10.11646/phytotaxa.447.3.7
Ana Gabriela Zacarías-Correa, Andrea D Wolfe, Esteban Manuel Martínez Salas, Marie-Stéphanie Samain: Penstemon reidmoranii (Plantaginaceae), a new species from Baja California, Mexico. In: Phytotaxa, Volume 387, Issue 1, Januar 2019. doi:10.11646/phytotaxa.387.1.5
