On the sum of normal matrices
This short paper revisits a remarkable but almost overlooked result of Djoković [Proc. Amer. Math. Soc. 27 (1971) 19-23]. A connection to a result of uSemrl is pointed out. With Djoković's result, an extension of Craig-Sakamoto theorem to $k$ ($k\ge 2$) normal matrices is presented. A comment to a recent monthly problem is also given.