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

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

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]>>>.