[Dr. Sivana]

Del Shannon’s “Sue’s Gotta Be Mine” also tells his girl to not worry what people will say, and that he’ll get a job and work every day. Several sources claim the song has a Four Seasons sound to it. I don’t hear it myself, and Del was doing falsettos before there was a Four Seasons.

You can decide:
https://www.youtube.com/watch?v=i1j8ek7Hsmo

[Fiji Hill]

The singer is definitely Del Shannon. However, the Four Seasons moonlighted under the name The Wonder Who and waxed Don't Think Twice, It's All right in 1965.