Winai Somprasong และ Parikarn Surapanpichit; Pranai Penchit. (2004) Studies and Collection of Ferns and Their Allies in the Phu Wiang National Park, Khon Kaen Province. <i>Thai Agricultural Research Journal</i>, <i>22</i>(2), 96-109.Winai Somprasong และ Parikarn Surapanpichit; Pranai Penchit. "Studies and Collection of Ferns and Their Allies in the Phu Wiang National Park, Khon Kaen Province". Thai Agricultural Research Journal 22 (2004):96-109.Winai Somprasong และ Parikarn Surapanpichit; Pranai Penchit. Studies and Collection of Ferns and Their Allies in the Phu Wiang National Park, Khon Kaen Province. Department of Agriculture:ม.ป.ท. 2004.