Coba jelasin Bacaan lanjut dari Racun rumpai dalam bahasa melayu dong

3. Homer M. LeBaron, Janis E. McFarland and Orvin C. Burnside, The Triazine Herbicides: 50 years Revolutionizing Agriculture,2008, ISBN: 978-0-444-51167-6

4.  The History of Roundup  http://roundup.ca/en/rounduphistory