The links to the Geoidal Models can be found via the Knowledge Base Topics or from the links below
Australia Geoids
topic_id=1209
EGM08 Geoid
topic_id=1307
India Geoids
topic_id=1306
Korea Geoids
topic_id=1301
Malaysia Geoid - Sabah and Sarawak
topic_id=1335
New Zealand Geoids
topic_id=1276
Singapore Geoid
topic_id=1333
Thailand Geoids
topic_id=1297
Timor-Leste EGM96 Geoid
topic_id=1338