Complex sentence: Finland had 78 numbers (mostly with new Batet illustrations), the original editions in Norway, Denmark and Sweden had identical covers (with special unique covers for these three countries-the illustrations often ranked as the finest-and most probably Batet's).
Split into simpler sentences: Finland had 78 numbers (mostly with new Batet illustrations). The original editions in Norway, Denmark and Sweden had identical covers (with special unique covers for these three countries-the illustrations often ranked as the finest-and most probably Batet's).