According to § 22 in the Danish law on copyright:
" A person may quote from a work
which has been made public in accordance with proper usage
and to the extent required for the purpose"
This rule always applies, no matter how old the work that you want to quote from is.
You should always quote correctly and loyally, and state your source.
It is only in special cases that you are permitted to quote a work in its full length.
For example, you are allowed quote a poem in connection with a critical discussion of it.
For further information, please contact Line Kronqvist Jensen or Jens Dam at the library.