Text books:

1.  Cappuccino G .James, Sherman Natalie, Microbiology A laboratory manual, seventh edition, Pearson Education
2. Brown E. Alfred, Benson’s Microbiological Applications, ninth edition, McGraw Hill Publication
3. Pelczar J. Michael, Chan E.C.S, Krieg R. Noel, Microbiology, fifth Edition, Tata McGraw-Hill Publishing Company Limited
4. Prescott M. Lansing, Harley P. John, Klein A. Donald, Microbiology, sixth edition, McGraw-Hill Higher Education
5. Ananthanarayanan R, Text book of microbiology, sixth edition, Longman Private Limited
    

Webliography:

1. http://www.ncl.ac.uk/dental/oralbiol/oralenv/tutorials/gramstain.htm
2. http://en.wikipedia.org/wiki/Gram_staining
3. http://www.scienceprofonline.org/gramstainingbacterialidentificationofgra
4. Differential Stains for Identifying Bacteria
5. http://www.microbelibrary.org/microbelibrary/files/ccImages/Articleimages/shoeb/Gram.html