“Effect of Exudates Excreted by Trichoderma Harzianum on the Nitrogen Fixation (C2H2- Reduction) Rate of the Cyanobacteria Anabaena Variabilis ”. Journal of Madenat Alelem 1, no. 1 (June 30, 2009): 21–28. Accessed February 24, 2026. https://journal.mauc.edu.iq/index.php/JMAUC/article/view/290.