Given a character matrix, your task is to identify the positions of all squares with a length of at least 3 and output the row and column numbers of the bottom-right corner of these squares. The squares are composed of the same character, and each side has a length of at least 3.

If the matrix is

G Y A D H G C P H F E E F G F
X K G F T E D D E Y H N J R P
V L B F A I I I I H O N O R H
E N G U Z I I I I W J O M V F
J E M F U I I I I A Y B T F E
D R A H R I I I I X R M I S R
O O O C X X O R F F K L Y G N
P R X Y M G W L G A R B G I F

Please provide the row and column of the bottom-right vertex of the square in the character matrix with a side length of at least 3 (the answer is unique). Notice: All coordinates start from 0.  

Your answer should be in the format <<<[row, column]>>>.