Extract the names of the groups of islands located on the Azores plateau from the text. Separate them with a comma.

These islands can be divided into three recognizable groups located on the Azores Plateau:
The Eastern Group (Grupo Oriental) of São Miguel, Santa Maria and Formigas Islets
The Central Group (Grupo Central) of Terceira, Graciosa, São Jorge, Pico and Faial
The Western Group (Grupo Ocidental) of Flores and Corvo.

Eastern Group, Central Group, Western Group