1. ^{{cite web|url=https://books.google.com/books?id=rk0QwMXRrNcC&pg=PA56&dq=%22Dakota+Burl%22&hl=en&sa=X&ved=0ahUKEwijqcCY94nfAhULC6wKHUimCSkQ6AEIMjAB#v=onepage&q=%22Dakota+Burl%22&f=false|title=Material Revolution: Sustainable and Multi-Purpose Materials for Design and Architecture|first=Sascha|last=Peters|date=5 November 2012|publisher=Walter de Gruyter|via=Google Books}}
2. ^{{cite web|url=https://books.google.com/books?id=IB5p-DmGkAEC&pg=PA76&dq=%22Dakota+Burl%22&hl=en&sa=X&ved=0ahUKEwijqcCY94nfAhULC6wKHUimCSkQ6AEIODAC#v=onepage&q=%22Dakota+Burl%22&f=false|title=Green Restorations: Sustainable Building and Historic Homes|first=Aaron|last=Lubeck|date=1 January 2010|publisher=New Society Publishers|via=Google Books}}
3. ^{{cite web|url=https://books.google.com/books?id=SCbf0ZMwcr8C&pg=PA212&dq=%22dakota+burl%22&hl=en&sa=X&ved=0ahUKEwjR4pet_YnfAhWEJDQIHTv4DQgQ6AEIPjAD#v=onepage&q=%22dakota+burl%22&f=false|title=Green Building Products, 3rd Edition: The GreenSpec® Guide to Residential Building Materials--3rd Edition|first1=Alex|last1=Wilson|first2=Mark|last2=Piepkorn|date=1 March 2009|publisher=New Society Publishers|via=Google Books}}
4. ^{{cite web|url=http://www.mankatofreepress.com/news/local_news/environ-biocomposites-plant-is-idle/article_fb457a9d-ae8d-591a-b1ae-a69d5f5e81fb.html|title=Environ Biocomposites plant is idle|first=Dan NienaberThe Free|last=Press|website=Mankato Free Press}}