(S (S (S (NP (EX There)) (VP (VBZ is) (NP (BASENP (DT some) (NN disagreement)) (PP (VBG regarding) (NP (BASENP (DT the) (NNS methods)) (PP (IN of) (NP (BASENP (NN measurement)) (VP (VBN used) (ADVP (RB previously)))))))))) (COMMA ,) (SBAR (IN so) (S (BASENP (DT the) (NNS researchers)) (VP (VP (VP (VBD spent) (BASENP (DT an) (NN hour))) (PP (IN at) (BASENP (DT the) (NN summit)))) (S (VP (VP (VBG taking) (BASENP (NNS measurements))) (S (VP (VP (VBG using) (NP (NP (BASENP (NN radar)) (COMMA ,) (BASENP (NN satellite))) (CONJP (COMMA ,) (CC and)) (BASENP (JJ other) (NNS methods)))) (PP (IN on) (BASENP (NN 6) (NNS points))))))))))) (PERIOD .))