Analysis of the type material of Achnanthes minutissima var. macrocephala (Bacillariophyta) and description of two new small capitate Achnanthidium species from Europe and the Himalaya
C. E. Wetzel, I. Jüttner, S. Gurung, and L. Ector
Plant Ecology and Evolution, vol. 152, no. 2, pp. 340-350, 2019