Horns on export emd and alco locomotives from 1950s to 1990s

Hi there everyone, I am digging into horns used on export model EMD locomotives G8, G12, G16 , GT16 and ALCO DL500,etc as I am aware that mostly Leslie and Nathan modified ones were used such as Nathan K2,Leslie Supertyfons S2 or modified two chime ones. Can anyone shed some more light on this.