Equal Sums

A B C
---. D
G F E
H
I

Each of the digits 1,2,3,4,5,6,7,8, and 9 is:
[1] Represented by a different letter from A to I. (Not necessarily in same order)
[2] Each of A+B+C, C+D+E, E+F+G, and G+H+I is equal to 13.
Which digit does E represent?
{Level-Medium}