The Monkees famously closed their second season Christmas episode with a performance of "Riu Chiu," a traditional Spanish carol dating from the 16th century.
An official studio version was recorded in October 1967, featuring Monkees producer Chip Douglas on vocals who was substituting for an absent Davy Jones. It went unreleased until 1990's Missing Links Volume Two.
It is likely that The Monkees learned the song from Chip Douglas, who himself performed it with his former band The Modern Folk Quartet on their 1964 album Changes.
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