Funny thing about that web site....
http://home.ica.net/~birch/paphs.htm
8th plant down the list:
Paph. Delrosi - rothschildianum 'Charlesbourg' X delenatii (vietnamese)

They can't decide if they used Paph. Delrosi or vietnamese?

Paph. vietnamense is the species... a little snooping on the web seems
to indicate there is a Paph. delanatii 'vietnamese'. Really?

Steve