* asia, backzone: Verify Trần 2005 and add sources.

I obtained a copy of Trần Tiến Bình's 2005 book "Lịch Việt Nam:
thế kỷ XX-XXI (1901-2100)", verified that www.thoigian.com.vn's
page is a verbatim quote of a passage in pages 45-50, and added a
list of Trần's sources for his pp 49-50.
* NEWS: Move abbreviation commentary to appropriate section.
* tz-art.htm: Add Enright play.  Fix Dylan title.
* tz-link.htm: Remove mention of no-longer-distributed USGS data.

Clean up typography slightly.