Catholic Encyclopedia
St. Magnus, also called Magnoaldus, Maginaldus, or Mang. His "life" was re-edited twice, so that he is said in it to be a contemporary of St. Gall (early seventh century) but also of the first bishop of Augsburg (mid-eighth century).
For All the Saints
Three short sentences, which opt for St. Magnus as a contemporary of SS. Gall and Columbanus.