1971 U.S. Professional Indoor
The 1971 U . S . Professional Indoor was a WCT and Virginia Slims Circuit tennis tournament played on indoor carpet courts . 
<triplet> 1971 U.S. Professional Indoor <subj> 1971 <obj> point in time <subj> carpet court <obj> surface played on <triplet> Virginia Slims Circuit <subj> tennis <obj> sport <triplet> carpet court <subj> tennis <obj> sport