Worm drive. Very similar to those from the various Norma group brands, so they're probably the OEM.
Predominant type in the cars up to the late 90s, large and small, until the cooling system hoses switched to plastic interlocking fittings.
The power steering reservoirs (and rack boots) had Oetiker clamps, which could seep and leak as they aged. Replaced with worm clamp and no issues afterward.
Can't think of any instances of spring clamps, at least in the older models.
Where I've touched the fuel system, I switched to the fullly smooth band nut/bolt clamps from ABA, which are much nicer for the smaller diamters (8 x 13mm fuel hose).