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

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

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]>>>.