History - Laetamini

Sep 09, 2019 (nokel81)

Added Liber Usualis as source

sources
[{"chant_id":"786","source":"2","page":"415","sequence":"2","extent":"1"},{"chant_id":"786","source":"2","page":"456","sequence":"1","extent":"1"},{"chant_id":"786","source":"2","page":"592","sequence":"1","extent":"1"},{"chant_id":"786","source":"3","page":"1337","sequence":"1","extent":"1"}]