• Nitrogen content and trends in agricultural catchments in EstoniaIital, Arvo; Klõga, Marija; Pihlak, Margus; Pachel, Karin; Zahharov, Andre; Loigu, EnnAgriculture, ecosystems and environment2014 / p. 44-53 : ill https://doi.org/10.1016/j.agee.2014.03.010 https://www.scopus.com/sourceid/15110 https://www.scopus.com/record/display.uri?eid=2-s2.0-85027929085&origin=inward&txGid=866585d09fdf83ad95ee4a5d00d5a110 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=AGR%20ECOSYST%20ENVIRON&year=2014 https://www.webofscience.com/wos/woscc/full-record/WOS:000347585100006