For at one and the same time Ptolemy sailed to Greece with a great fleet and tried to bring it to revolt, while Lysimachus invaded Macedonia from Thrace, and Pyrrhus from the neighbouring Epeirus, and both plundered the land. But Demetrius left his son in charge of Greece, while he himself, hastening to the rescue of Macedonia, set out first against Lysimachus. But tidings came to him that Pyrrhus had taken Beroea.
Edition :
Plutarch. Plutarch's Lives. with an English Translation by. Bernadotte Perrin. Cambridge, MA. Harvard University Press. London. William Heinemann Ltd. 1920. 9.
Remark :
date: The date is taken from the New Pauly.
http://referenceworks.brillonline.com/entries/brill-s-new-pauly/demetrius-e314200 longtermconsequence: Demtrius' army mutinies before he can attack either Pyrrhus or Lysimachus. This is mentioned in 44.3.
