|-
|align = "center" bgcolor = "#9BBB59" rowspan = "2"|'''1'''
|align = "center" rowspan = "2"|'''Schlumberger'''
|<font color="#0000FF"><u>[http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.htm&r=1&f=G&l=50&s1=7380602.PN.&OS=PN/7380602&RS=PN/7380602 US7380602B2]</u></font>
|Treating a subterranean carbonate with a fluid comprising of an acid, chelating agent, or betaine surfactant.