R.D. Klein - Company site of R.D. Klein, one of the makers of Ports of Call. The site offers program information, screenshots, and FAQs. - http://www.rdklein.com/ports_of_call/ports_of_call.html
Ports of Call - Trade- and shipping simulation game by Rolf-Dieter Klein and Martin Ulrich. - http://www.portsofcall.de/