Black, J.G.and Black, L.J.2008. Microbiology : princeples and explorations.7th ed.John Wiley, New Jersey.846 p. Talaro, K.P.2008.Foundations in Microbiology.6th ed.Mc Graw-Hill, Boston.834 p. Engelkirk, P.G., Duben-Engelkirk, J.L.and Burton, Gwendolyn R.W.2011.Burton microbiology for the health sciences. 9 ed. Lippincott Williams & Wilkins, Philadelphia. Talaro.2008.Foundations in Microbiology.6 thed.Mc Graw-Hill, Boston.834 p. Willey, Sherwood.2014.Prescott Engelkirk.2011.Burton