Textbooks

1. Prescott.L.M, Microbiology, McGraw Hill Publication (2005)18-22
2. Pelczar.J.M, Microbiology, Tata McGraw Hill Publication (1993)50-53
3. Pommerville.J.C, Alcamo's Fundamentals of Microbiology, Jones and Bartlett Publication (2004)101-108
4. Tortora.G.J, Microbiology, Pearson Education Publication (2004)54-57

Webliography

http://microbiology.suite101.com/article.cfm/what_is_a_compound_light_microscope
http://biology.clc.uc.edu/fankhauser/Labs/Microscope/Oil_Immersion.htm
http://www.microscopyu.com/articles/formulas/index.html
http://inventors.about.com/od/mstartinventions/a/microscope.htm