I checked an old thread about the logic of Child ballad organization but found no answer to my question. I understand that the ballads are numbered and the variants are lettered, "78C," for example. what does it mean if the upper case variant letter is followed by a lower case letter? For example, #78 (The Unquiet Grave)has 8 variants, 78A-78H. However, H is subdivided into 78Ha, 78Hb, and 78Hc. What is the distinction between upper and lower case identifications?