CDC (1986): Epidemiologic Notes and Reports Occupational Fatality Following Exposure to Hydrogen Sulfide—Nebraska, 1992. Morbidity & Mortality Weekly Reports (MMWR) 35:(33):533-535.
Brubaker B. 2007. Four family members, farmhand killed by gas fumes in manure pit. The Washington Post, July 7, 2007. http://www.washingtonpost.com/wp-dyn/content/article/2007/07/03/AR2007070302136.html
Beaver RL, Field WE. Summary of documented fatalities in livestock manure storage and handling facilities – 1975-2004. J Agromedicine. 2007;12:3–23. doi:10.1300/J096v12n02_02.
ASAE EP 470.1. Manure Storage Safety. St. Joseph, MI 49085: American Society of Agricultural and Biological Engineers; October 2011. (R 201)