Given the task definition and input, reply with output. Generate a correct and concise answer for the question based on the words in the context.

Context : Matilda of Holstein or Mechthild (1220 or 1225 -- 1288 in Kiel) was a Danish queen consort, married to King Abel of Denmark and later to Birger Jarl, Regent of Sweden.
Question : What is Matilda of Holstein's spouse's name?
Abel of Denmark