A Phoenix woman had no idea a $3 purchase from Goodwill would turn out to be a rare link to the civil rights movement's most revered leader.
Last April, Mary Scanlon bought a pile of 35 vintage reel-to-reel tapes, including one with the Rev. Martin Luther King Jr.'s name on it.
Arizona State University archivists have found that tape is the only known recording of speeches the slain civil rights leader gave at ASU and at a Phoenix church in June 1964.
The hour-long audio is now available for listening on ASU's website through June 30.
The tape illustrates that King had been eager to visit supporters in Arizona, a state that would draw criticism more than 20 years later for rescinding the Martin Luther King Jr. holiday.
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