1. Variations in the organic reserves in underground parts of five perennial weeds from late April to November;Arny;Univ. of Minnesota, Agr. Exp. Stat. Technical Bull.,1932
2. Bakker , D. 1951 Oecologie van klein hoefblad , Tussilago farfara L., en de bestrijding van deze plant in de Noordoostpolder Groningen
3. Bakker , D. 1960 A comparative life-history of Cirsium arvense (L.) Scop. and Tussilago farfara L., the most troublesome weeds of the newly reclaimed polders of the former Zuiderzee J. L. Harper The biology of weeds 205 222 Oxford
4. Bosman , M. S. M. 1953 De bepaling van oplosbare suikers in gras Wageningen
5. La genèse des lévulosans chez les végétaux;Colin;Bull. Soc. Chim. Biol.,1925