As I've told you I'm currently working on mapping the database of my current ILS (CDS/ISIS, CEPAL layout) to MARC21, to import it to koha. I've managed to generate MARC records form the exported data of my ILS. I've downloaded today the Koha DB Schema, what we want to insure is that for every title we have one record is added to the biblio table, no matter how many copies of this title we have, also we want to have as many items as copies we have for each title. In order to achieve this goals we are trying to understand the way bulkmarcimport.pl handles MARC records, in order to feed it with properly loaded records. It's not clear for me the way i have to build my MARC records, in order to represent fully the reality I've presented you above. Any help will be appreciated. Andrés