Dourson. Wildflowers and Ferns of Red River Gorge and the Greater Red River Basin. The University Press of Kentucky.
Citazione stile Chigago Style (17a edizione)Dourson. Wildflowers and Ferns of Red River Gorge and the Greater Red River Basin. The University Press of Kentucky.
Citatione MLA (9a ed.)Dourson. Wildflowers and Ferns of Red River Gorge and the Greater Red River Basin. The University Press of Kentucky.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.