Gamle USA Public Domain e-bøger? Copyright eller ikke i Danmark?

Jeg fandt ved et tilfælde (serendipitet) følgende site med gamle tekniske e-bøger (skannede gamle bøger) om elektronrør, transistorer og kviksølvensrettere osv.:
http://www.tubebooks.org/
Citat: "...
Technical books online!
4.22 gigabytes and still (slowly) growing! Over 100 titles!
...
I've found that most of the technical books published before about 1964 never had their copyrights renewed, so now are in the public domain. So I am endeavoring to digitize and post some selected books relating to the "vacuum tube age" of electronics here.
..."

Amateur Radio.
Publications of historical importance rescued from obscurity and posted on the web for the benefit of all hamkind:
http://n4trb.com/AmateurRadio/HamDocs.htm

Spørgsmålet er så, hvis de er public domain i USA, er de vel også public domain i EU (incl. Danmark)?

How Can I Tell Whether a Copyright Was Renewed?:
http://onlinebooks.library.upenn.edu/renewals.h tml
Citat: "...
First of all, you need to know when renewal matters. In the US, books published before 1964 had to get their copyrights renewed at the Library of Congress Copyright Office in their 28th year, or they'd fall into the public domain. Some books originally published outside the US by non-Americans are exempt from this requirement, and in fact some such books had their copyrights restored recently. If you need to know more about the rules for books published outside the US, see this page from the Copyright Office, explaining recent changes in copyright law imposed by GATT. Basically a work is exempt from renewal requirements if all of the following conditions apply:
* At least one author was a citizen or resident of a foreign country (outside the US) that's a party to the applicable copyright agreements. (Almost all countries are parties to these agreements.)
* The work was still under copyright in at least one author's "home country" at the time the GATT copyright agreement went into effect for that country (1 January 1996 for most countries).
* The work was first published abroad, and not published in the United States until at least 30 days after its first publication abroad.

If you can prove any of these conditions don't apply, and the work was originally published or copyrighted before 1964, then the work had to be renewed in order to stay copyrighted in the US.
..."

Svar til #1:
Jeg ved ikke om det stadig gælder. Jeg har lært at er en bog udsolgt fra forlaget, må man kopiere til eget privat behov!
vh erik