Sorry to reply so late, I was not online for some time...
If I remember correctly, I have used Ansco 79b formula from http://unblinkingeye.com/Articles/LithDev/lithdev.html (it could be also Kodak D-85, I have tested both).
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links. To read our full affiliate disclosure statement please click Here.