(S (SBAR (IN Although) (S (BASENP (DT this) (NN letter)) (VP (VP (VBD did) (RB not)) (VP (VB say) (SBAR (WHNP (WDT which) (QT (DQL ``) (NNS superiors) (DQR ''))) (S (BASENP (NNP Libby)) (VP (VBD referred) (PP (TO to))))))))) (COMMA ,) (S (BASENP (DT the) (NNP National) (NNP Journal)) (VP (VP (VBD reported) (PP (IN on) (BASENP (NNP Thursday)))) (SBAR (IN that) (S (BASENP (PRPD their) (NNS sources)) (VP (VBD said) (SBAR (S (BASENP (DT this)) (VP (VBD included) (NP (BASENP (PRPD his) (JJ immediate) (NN boss)) (COMMA ,) (BASENP (NNP V.P.))))))))))))