The online documentation for the DASILVA dataset refers to the original distribution of the surface marine atlas (1945-1989).
Subsequently, two supplements were added. One includes the data for 1990-1993 and the other is a set of 1/2 x 1/2 climatologies. I am not aware of any online documentation for these additional data. However, the publications "ASMD94 Supplement A - Anomalies of Directly Observed Quantities & Surface Marine Fluxes for 1990-93" and "ASMD94 Supplement B - "Procedures for 1/2 degree x 1/2 degree Data Set" are available for purchase here.
-- Michael Bell