Zarina, Livija; Gerowitt, Bärbel; Melander, Bo; Salonen, Jukka; Krawczyk, Roman and Verwijst, Theo    (2015) Crop diversification for weed management in organic arable cropping systems.   In:     Proceedings of the 10 th International Scientific and Practical Conference, Rēzeknes Augstskola, Rezekne, 2, pp. 333-336.