Prinicipal surjit singh has written excellent article about Guru satguru according to gurbani
http://www.sikhmarg.com/2007/1021-gurbani-anusaar-guru.html
Those who can read gurmukhi should must read it
http://www.sikhmarg.com/2007/1021-gurbani-anusaar-guru.html
Those who can read gurmukhi should must read it