Bruce posted the tune (in abc format) given by Motherwell in this earlier discussion:  Bonnie Susie Cleland -- Different Tune.  It is the one used by Jean Redpath (and no doubt a great many others who have learned it from her record) and is probably more familiar than the one in the DT, which was transcribed from the singing of one Lisa Null; there is no indication as to where Ms. Null got it, and the tune Sorcha found through JC was extracted by Martin Doering from the DT and transcribed into abc from the midi in the file here, so that doesn't give any additional information.  Abc can be converted easily into staff notation through a number of shareware programs; info available through the FAQ.

Malcolm