Lincoln's views on his mother's ancestry

[Gene C]

Vicky, I kind of have gotten lost somewhere in all of this.
If I understand correctly, we are discussing who AL's grandfather on his mother's side might be. The grandmother's name is Lucy?

Who do you say was AL's grandfather on his mother's side (Nancy's father), and who or what is the documentation or evidence to support it, and where can the original documents or sources be found?