1. There are many textbooks describing different aspects of the basic interactions in nature. A good phenomenological introduction to this field can be found in D.H. Perkins, Introduction to high energy physics (Addison-Wesley Publishing Company, 1987). A more theoretical approach is taken by T.-P. Cheng and L.-F. Li, Gauge theory of elementary particle physics (Oxford University Press, 1984) as well as by C. Itzykson and J.-B. Zuber, Quantum field theory (McGraw-Hill International Book Company, 1980).
2. Perhaps the best didactic introduction to the theory of gravitation and the general theory of relativity is C.W. Misner, K.S. Thorne and J.A. Wheeler, Gravitation (W.H. Freeman and Company, 1973).
3. Several introductions to this field and review articles have been written. The basics are described e.g. by M. Creutz, Quarks, gluons and lattices (Cambridge University Press, 1983). Contributions written by some of the leading scientists in this fields have been collected in M. Creutz (editor), Quantum fields on the computer (World Scientific, 1992).
4. L. Susskind, Phys. Rev. D16 (1977) 3031.
5. K. Wilson, in New Phenomena in Subnuclear Physics, edited by A. Zichichi (Plenum Press, 1977).