15N-labeled glyphosate synthesis and its practical effectiveness - Tavares, Claudinéia Raquel de Oliveira; Bendassolli, Jose Albertino; Ribeiro, Daniela Neves; Rossete, Alexssandra Luiza Rodrigues Molina; Prestes, Clélber Vieira; Tavares, Glauco Arnold (Scientia Agricola, 2010)