Period 09 : The length of time between two successive tsunami wave peaks or troughs. May vary due to complex interference of waves. Is usually measured in minutes
New South Wales Government, New South Wales Tsunami Emergency Sub Plan, A Sub Plan of The New South Wales Disaster Plan (Displan),Glossary, Director of Emergency Risk Management, State Emergency Service, State Headquarters,Wollongong, New South Wales NSW, Australia 2008. http://www.tsunamisafe.com.au/glossary-of-terms, (ND/ Tsunami Emr - Brit) {958}