refs-processed.bib:
perl -p -e 's/©//' refs.bib > refs-processed.bib
perl -0pe 's/,\s+(file|abstract) = \{.*?\}(,\n|\n)/\2/sg' refs-processed.bib |sponge refs-processed.bib
recode -d u8..ltex < refs-processed.bib | sponge refs-processed.bib
refs-processed.bib:
perl -p -e 's/©//' refs.bib > refs-processed.bib
perl -0pe 's/,\s+(file|abstract) = \{.*?\}(,\n|\n)/\2/sg' refs-processed.bib |sponge refs-processed.bib
recode -d u8..ltex < refs-processed.bib | sponge refs-processed.bib