HK - All of the campy hubs that I have around have the threading in small letters around the flat in front of the driveside flange, just before the threads...from Sheldon's site

Type Thread Specification Equivalent
I.S.O. 1.375" x 24 tpi 34.92 x 1.048 mm
British 1.370" x 24 tpi 34.80 x 1.058 mm
French 34.7 x 1 mm 1.366" x 25.4 tpi
Italian 35 mm x 24 tpi 1.378" x 1.058 mm
Metric BMX 30 mm x 1 mm 1.181" x 25.4 tpi

I think that if you spent some time looking you could find some additional sizes, but this list takes care of most of the possibilities.