1. Characteristics and modes of origin of weeds;Baker,1965
2. The evolution of weeds;Baker;Annual Review in Ecology and Systematics,1974
3. Prickly lettuce (Lactuca serriola) – a population explosion in Warwickshire;Bowra;BSBI News,1992
4. Distribution limits from a demographic viewpoint;Carter,1988
5. A neutral terminology to define “invasive” species;Colautti;Diversity and Distributions,2004