The prints edited by Andrea Antico are not listed on the composer pages on IMSLP. You have to look at the composer page (sic) of "Andrea Antico" instead and click on the tab "Collected Works". Unfortunately, the 1520 print is not listed there either.
The edition on CPDL, however, is not based on the Antico print, but on a beautiful manuscript source, "Anne Boylen's Songbook". The facsimile published by Alamire is out of print but a copy might be available in a number of libraries.
@Quaerens If you simply want to change the text underlay of an edition, you can easily do it with the annotation tool of many PDF viewers (Preview, Xournal, Acrobat Reader, ...). Simply choose the annotation "text" and select a white background instead of the default transparent background.
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