Dr Whitehead has written 2 published papers on earthquake precursor effects:

Results of the precursor survey were published in the Natural Hazards and Earth System Sciences journal. The paper is available from this site as a downloadable pdf and is more technical than the survey report.

Unusual Childhood Waking as a Possible Precursor of the 1995 Kobe Earthquake. Animals 2013, 3, 228-237; Motoji Ikeya, and Neil E. Whitehead.