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

F N U V P Q
C I I I V D
Y I I I M R
Z I I I S J
C N C H L O
O S A Z Y H
C E J R Y Z
X A V N P E
O K D Q Q I
E H G N P 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]>>>.