Dergiler / Mathematical Sciences and Applications E-Notes / 2017 / Cilt: 5 - Sayı: 2Exponentials of Sums of Operators in a Banach SpaceMichael GİL’DergiMathematical Sciences and Applications E-NotesSayı2017 · Cilt: 5 - Sayı: 2Sayfa45–50DOI—