Grimmett: Percolation.
Lyons & Peres: Probability on trees and networks, chapters 7-8.
Garban & Steif: Noise Sensitivity of Boolean Functions and Percolation.
Heydenreich & van der Hofstad: Progress in high-dimensional percolation and random graphs.
Werner: Random planar curves and Schramm-Loewner evolutions, chapter 10 (Saint-Fluor lecture notes or arXiv:0303354)
Bollobas & Riordan: Percolation