Writing CFG for Languages

Question

Write a CFG for the given language L:

L = { a^i * b^j * c^k | i=j or i=k. Consider i >= 0, j >= 1, k >=0 }

I came up with:

S → XY | W

X → aXb | ε

Y → cY | ε

W → aW c | Z

Z → bZ | ε