This is certainly incorrect. It *is* widely believed that Soviet texts dating prior to 1973 (when the USSR became party to the relevant convention) may be freely used and considered public domain, but this is almost certainly untrue from a legal standpoint, and copyrighted material produced subsequent to that date is as protected as this message (moreso, perhaps).

The relevant US law is Title 17, Chapter 1, Section 104

http://www4.law.cornell.edu/uscode/17/104.html

In essense, if the work was first published in a country which was not a party to a copyright agreement with the United States at the time, it is mostly likely not covered under US copyright law. Note that I only say most likely. I'm not a lawyer, and I'm not going to get into the nitty gritty details and exceptions. Also, the laws of other countries will likely differ.

Anthony