Overview of how Agrobacterium tumefaciens infects plants and causes disease. Published by APS. Crown gall by Kado, C.I. 2002. Crown gall. The Plant Health Instructor. DOI:10.1094/PHI-I-2002-1118-01
Excellent introducation to parastici plants.
Nickrent, D.L. and Musselman, L.J. 2004. Introduction to Parasitic Flowering Plants. The Plant Health Instructor. DOI: 10.1094/PHI-I-2004-0330-01