ECMA-48:
  http://www.ecma-international.org/publications/standards/Ecma-048.htm

Xterm Control Sequences:
  http://invisible-island.net/xterm/ctlseqs/ctlseqs.html

Digital VT100 User Guide:
  http://vt100.net/docs/vt100-ug/

Digital VT220 Programmer Reference Manual
  http://vt100.net/docs/vt220-rm/
