The International Fertiliser Society was founded in 1947 for individuals who have a professional interest in any aspect of fertiliser production, marketing and use. Membership is personal and is open to all and is drawn from almost 50 countries world-wide. The published Proceedings of the Society Meetings are one of the major publicly available sources of information on fertiliser production and use, and on crop nutrition...

Also IFS has available Themed collections of Society Proceedings like ammonia, ammonium nitrate and nitric acid. These are in digital pdf format on USB cards. 
Plus Recordings of presentations are available: These are comprised of an audio recording synchronised with the author’s charts and include the question and answer session. 

For example the presentation of Dr. Amit Roy of the International Fertiliser Development Council (IFDC) based in the USA entitled “Global fertiliser transitioning from volume to value“. “Amit’s paper will focus upon the new generation of fertilisers which are much more efficient in providing nutrients to crops with lower carbon foot-print and environmental impact” 
Link: https://vimeo.com/134630827 
Password: 2015Tech07