Cache is located at S 33 50.AB4 E 148 40.CD0
The missing co ordinates can be found by answering questions about this famous artwork and its famous artist.
A= First word in title of artwork. Number of letters. Subtract 3 from answer
B= Second word in title of artwork.Number of letters.add 1 to answer
C= Third word in title of artwork. Subtract 1 from answer
D= Surname of artist. Number of letters. Subtract 3 from answer.