CR <- c("ANDREOSSO-O'CALLAGHAN B, 2008, PALGRAVE STUD EUR UN, P61.   ALECU DE FLERS N, 2005, INT RELATIONS EUROPE, P317.   DUCHENE FRANCOIS, 1973, NATION WRIT LARGE FO.   KOH T, 2007, STRAITS TIMES   0808.   LENZ T, 2009, GEOPOLITICS GEOECONO.   LUCARELLI S, 2010, ROUTL GARN SER EUR W, V7, P1.   MANNERS I, 2002, J COMMON MARK STUD, V40, P235, DOI 10.1111/1468-5965.00353.   NYE J., 2004, SOFT POWER MEANS SUC.   ORBIE J, 2010, NORMATIVE POWER EURO.   PORTELA C, 2007, 200710 RSCAS.   ROSECRANCE R., 1998, PARADOXES EUROPEAN F.   SMITH K.E., 2003, EUROPEAN FOREIGN POL.   SONG XN, 2010, REV INT STUD, V36, P755, DOI 10.1017/S0260210510000835.   TANAKA T, 2008, PALGRAVE STUD EUR UN, P170.   WARLEIGH-LACK A., 2010, COMP REGIONAL INTEGR, P43.")
explain <- data.frame(CR)
pat <- "(?i)(^|\\.  +)NYE J\\.(?:(?!\\. {2}).)*?\\b2004\\b(?:(?!\\. {2}).)*?means suc(?:(?!\\. {2}).)*"
repl <- "\\1NYE J., 2004, SOFT POWER: THE MEANS TO SUCCESS IN WORLD POLITICS, NEW YORK: PUBLICAFFAIRS"
explain$CR <- gsub(pat, repl, explain$CR, perl=TRUE)
explain$CR

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