In Microsoft Exchange they are SMTP addresses with calendars.
So, while your export file names for Users should match the target SMTP address. the resource mapping file will actually map the ICS file name to the SMTP address.
For example, the export file:
erp conference room 1 tiger.ics
Side note: If you have parentheses in your Oracle Calendar Server resource name, for example:
ERP Conference Room 1 (Tiger)
Drop the parentheses or other nin-permitted characters and use the same mapping.