MERCER, Pa. (AP) - A founding member of the 60s vocal group, The Lettermen, is suing a former member in a western Pennsylvania court claiming he's violating the group's trademark by continuing to refer to the group and his music in his solo career.

The Herald of Sharon, Pa. reports a Mercer County judge is scheduled to hear a request for an injunction Monday by Tony Butala, who helped found the group, against Mark Preston, of York. Preston has spent two stints with the group, most recently leaving the group a second time in August.

Butala claims Preston is violating the group's copyright by using performance of the group's songs that Butala claims to own on Preston's web site, among other things.

Preston tells The Associated Press, "I don't think I'm doing that, but we'll let the courts take care of that this morning."

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