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

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]>>>.