Everton boss Dave Moyes and assistant Alan Irvine watched the game against Celtic this week, and are keen on signing Goalkeeper Christiansen and midfielder Silberbauer in January.
The Guardian says Silberbauer is valued at £2m and former Rangers goalkeeper Christiansen is valyed at £1.5m
Everton would like to sign Christiansen if Manchester United decides to recall goalkeeper Tim Howard, who is presently on loan on Merseyside.
