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

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

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]>>>.