Perhaps you should try some spelling variations:
kriging referencess » origin references, origins references, driving references
horizons references » hormones references, motions references, ions references
kriging references » origin references, origins references, driving references
year kriging » year writing, year origins, linear kriging
ear horizons » far horizons, near horizon, a horizons
a kriging » _ kriging, 3 kriging, 4 kriging

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: (( year kriging references ) OR ((( ear horizons references ) OR ( a kriging referencess )))).
• Adding a wildcard symbol may retrieve word variants: (( year kriging references ) or ((( ear horizons references ) or ( a kriging referencess ))))*.