This Bible contradiction is from the Skeptic's Annotated Bible.
Ezra 8:18 View context
And by the good hand of our God upon us they brought us a man of understanding, of the sons of Mahli, the son of Levi, the son of Israel; and Sherebiah, with his sons and his brethren, eighteen;
Genesis 46:11 View context
And the sons of Levi; Gershon, Kohath, and Merari.
1 Chronicles 6:1 View context
The sons of Levi; Gershon, Kohath, and Merari.
1 Chronicles 23:6 View context
And David divided them into courses among the sons of Levi, [namely], Gershon, Kohath, and Merari.