Matrix OperatersMatrix MultiplicationMatrix TraceMatrix SquareEinstein NotationMatrix derivative The Matrix cookbookwww.math.uwaterloo.cahttps://www.math.uwaterloo.ca/~hwolkowi/matrixcookbook.pdfia902808.us.archive.orghttps://ia902808.us.archive.org/0/items/philtrans05474612/05474612.pdf