Hanfling, D., Altevogt, B.M., Viswanathan, K., and Gostin, L.O. (eds.). (2012). Crisis Standards of Care: A Systems Framework for Catastrophic Disaster Response. Institute of Medicine. National Academies Press.
Chapter 7 of the framework, Hospitals and Acute Care Facilities, provides a high level of detail related to implementing surge strategies, including immediate bed availability.