Holter family in Christiana

http://digitalarkivet.arkivverket.no/ft/person/pf01036370002088 Looking to find birth records for Axel Fredrik Holter and his wife Dagmar Holst. where should I look for their baptism records or marriage records? According to the census they were both born in Christiana but how do I narrow it down? thank you for your help. Davidd