This post on the mobbing of a Grey Heron by Black-naped Terns (and associated images) has been incorporated into the publication below. Get a PDF copy of the paper HERE.
Deng, S. H., T. K. Lee & Y. C. Wee, 2008. Black-naped terns (Sterna sumatrana Raffles, 1822) mobbing a grey heron (Ardea cinerea Linnaeus, 1758). Nature in Singapore 1: 117-127.