An illustrated flora of the Northern United States, Canada and the British possessions
Britton, N.L. and Addison Brown
An illustrated flora of the Northern United States, Canada and the British possessions - - New York-USA New York Botanical Garden 1943 - v.1 - .
--Flora--USA--Canada--Colonias Britanicas--Ophioglossaceae--Polygonaceae--
Botanica
An illustrated flora of the Northern United States, Canada and the British possessions - - New York-USA New York Botanical Garden 1943 - v.1 - .
--Flora--USA--Canada--Colonias Britanicas--Ophioglossaceae--Polygonaceae--
Botanica