Who Was Telling The Truth, Who Was Lying

Alan said “Either Barbara or Deirdre Is lying.”

Barbara said “Either Colin or Deirdre is telling the truth.” 

Colin said “Either Alan and Deidre are both lying or Barbara is lying.”

Deidre said “Either Alan or Barbara is telling the truth.

Who was telling the truth, and who was lying?

Note: Here “or” is always meant in the inclusive sense. For example “Either Barbara or Deirde is lying” means “Either Barbara or Deidre is lying or both are lying.”