Apple Digital Masters
Loudness then & Loudness Now - What is Loudness Normalization in the 2020s?
What is a UPC/EAN and how do I get one ( a barcode to you and me)
What is an ISRC (International Standard Recording Code) and how do I get one?
How long can mastering take?
What is Mastering for CD?
Why you should not send compressed mixes to your mastering engineer...