HR is a vast field and there is no author which u can say is the guru of whole field. Anyways following are the books that can definitly help u. But ppl should keep in mind that these are the Academic Journals that can makes a difference.Anyways the list is as following:
1- HRM . 10th ed, by Michael Armstrong
2- Remuneration and Performance Management by Michael Armstron & Helen Murlis
3- Strategic Safari by Henry Mintzber, 2004/05
4- HRM: Theory & Practice by John Bratton & Jeff Gold, 4th ed, 2007
5- HRM (Australian Ed) by Kramar et al.
6- Strategic Marketing management by David Aaker, 8 ed, 2007
7- Org. Behaviour by Robbins et al, 4 ed, 2004