He regards this rather unfortunately named custom of the levirate as having its root in group marriage.
"Kinship Organisations and Group Marriage in Australia" by Northcote W. Thomas
This story is chiefly of interest to us as it shows the continuation, even into the period of exile, of the Levirate marriage custom.
"Oriental Women" by Edward Bagby Pollard
This is certainly possible, although it rests on the hypothesis of the Levirate marriage.
"A Harmony of the Gospels for Students of the Life of Christ" by Archibald Thomas Robertson
The custom of the Levirate mentioned in Deut.
"Bible Studies" by Joseph M. Wheeler