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OUR RECOMMENDATION: Try the on-line lookup (the 
at the top or the * are used to get the Notes) as it can be the fastest way to look up access a code, but call us old fashioned, we would still recommend downloading the HTML 5 single document code list. The great thing about a unified document is Both it and the on-line look up are unified documents that you can search it for terms . An (an example would be finding which Lists reference "Bestseller" – and finding the term leads you to Code List and that can be found in the Specifications and the ONIX structure that supports it.which can be used to find out where it's used Specifications) but the HTML 5 version displays everything at a glance. Arguably so does the on-line version – so maybe we're old fashioned – but try both and read the notes!
But whatever you do you should always use Specifications and Best Practices with their linked HTML code pages. That way you always have the right code at your fingertips – with the Notes that explain when to use it.
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