http://www.beltina.org/health-dictionary/bacteria-definition-types-what-is-list.html
http://www.pearsonsuccessnet.com
http://www.microbiologyonline.org.uk/about-microbiology/introducing-microbes/archaea
http://sgugenetics.pbworks.com/w/page/31659967/Known%20Molecular%20Features%20that%20differentiate%20Archaea
http://www.pearsonsuccessnet.com
http://www.microbiologyonline.org.uk/about-microbiology/introducing-microbes/archaea
http://sgugenetics.pbworks.com/w/page/31659967/Known%20Molecular%20Features%20that%20differentiate%20Archaea