Actually, I've been led to believe this sort of thing, under US law, is PD-US- certainly Sibley thinks so or they wouldn't have hosted it on their site. The lack of a date on the copyright notice would be the reason, I think. However, I'm no expert... Eric 04:16, 12 February 2011 (UTC)
Makes sense. Eric 04:25, 12 February 2011 (UTC)
