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

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

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]>>>.