Avril Lavigne faces a lawsuit by the members of a 1970s rock band who claim her hit song "Girlfriend" rips off one of their tunes.

Songwriters Tommy Dunbar and James Gangwer alleged in a lawsuit filed in U.S. District Court that Lavigne and her co-writers lifted their 1979 song "I Wanna Be Your Boyfriend," which was originally performed by Dunbar's new-wave band the Rubinoos.

"We are not so naive as to chalk it up to some sort of cosmic coincidence," Dunbar said in a statement Thursday. "The lyric, the meter, the rhythm — they're identical."

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The first court date has been set for Aug. 28 in Oakland.

A spokeswoman for Lavigne declined comment.

Videos comparing Lavigne's song with the Rubinoos' tune were among the most popular on YouTube Friday. Nearly half a million people had watched various clips highlighting the similarities between the songs.

• Click here to watch one of those YouTube clips.

The lawsuit is not the first mention of the similarities between the songs.

Music critic Stephen Thomas Erlewine, in a review published on Billboard magazine's Web site, noted that the chorus of "Girlfriend" was a "total lift from the Rubinoos' 'I Wanna Be Your Boyfriend.'"

• Click here to read the review.

The Rubinoos toured and recorded from 1975 to 1983 and had a hit with a cover version of Tommy James and the Shondells' "I Think We're Alone Now." They also wrote the theme song for the movie "Revenge of the Nerds."