@@ -710,7 +710,7 @@ class DFGLS(UnitRootTest):
710710    appears to be a unit root. 
711711
712712    DFGLS differs from the ADF test in that an initial GLS detrending step 
713-     is used before a trend-less ADF regression is run [1]_ . 
713+     is used before a trend-less ADF regression is run. 
714714
715715    Critical values and p-values when trend is 'c' are identical to 
716716    the ADF.  When trend is set to 'ct, they are from ... 
@@ -737,8 +737,8 @@ class DFGLS(UnitRootTest):
737737
738738    References 
739739    ---------- 
740-     .. [1 ] Elliott, G. R., T. J. Rothenberg, and J. H. Stock. 1996. Efficient 
741-       bootstrap for an autoregressive unit root. Econometrica 64: 813-836 
740+     .. [* ] Elliott, G. R., T. J. Rothenberg, and J. H. Stock. 1996. Efficient 
741+             bootstrap for an autoregressive unit root. Econometrica 64: 813-836 
742742    """ 
743743
744744    def  __init__ (self , y , lags = None , trend = 'c' ,
@@ -873,17 +873,17 @@ class PhillipsPerron(UnitRootTest):
873873    Notes 
874874    ----- 
875875    The null hypothesis of the Phillips-Perron (PP) test is that there is a 
876-     unit root, with the alternative that there is no unit root [1]_ . If the pvalue 
876+     unit root, with the alternative that there is no unit root. If the pvalue 
877877    is above a critical size, then the null cannot be rejected that there 
878878    and the series appears to be a unit root. 
879879
880880    Unlike the ADF test, the regression estimated includes only one lag of 
881881    the dependant variable, in addition to trend terms. Any serial 
882882    correlation in the regression errors is accounted for using a long-run 
883-     variance estimator (currently Newey-West [2]_ ). 
883+     variance estimator (currently Newey-West). 
884884
885885    The p-values are obtained through regression surface approximation from 
886-     MacKinnon (1994) using the updated 2010 tables ([3]_, [4]_) . 
886+     MacKinnon (1994) using the updated 2010 tables. 
887887    If the p-value is close to significant, then the critical values should be 
888888    used to judge whether to reject the null. 
889889
@@ -915,22 +915,22 @@ class PhillipsPerron(UnitRootTest):
915915    References 
916916    ---------- 
917917    .. [*] Hamilton, J. D. 1994. Time Series Analysis. Princeton: Princeton 
918-        University Press. 
918+             University Press. 
919919
920-     .. [2 ] Newey, W. K., and K. D. West. 1987. "A simple, positive 
921-        semidefinite, heteroskedasticity and autocorrelation consistent covariance 
922-        matrix". Econometrica 55, 703-708. 
920+     .. [* ] Newey, W. K., and K. D. West. 1987. "A simple, positive 
921+             semidefinite, heteroskedasticity and autocorrelation consistent covariance 
922+             matrix". Econometrica 55, 703-708. 
923923
924-     .. [1 ] Phillips, P. C. B., and P. Perron. 1988. "Testing for a unit root in 
925-        time series regression". Biometrika 75, 335-346. 
924+     .. [* ] Phillips, P. C. B., and P. Perron. 1988. "Testing for a unit root in 
925+             time series regression". Biometrika 75, 335-346. 
926926
927-     .. [3 ] MacKinnon, J.G. 1994.  "Approximate asymptotic distribution 
928-        functions for unit-root and cointegration bootstrap".  Journal of 
929-        Business and  Economic Statistics. 12, 167-76. 
927+     .. [* ] MacKinnon, J.G. 1994.  "Approximate asymptotic distribution 
928+             functions for unit-root and cointegration bootstrap".  Journal of 
929+             Business and  Economic Statistics. 12, 167-76. 
930930
931-     .. [4 ] MacKinnon, J.G. 2010. "Critical Values for Cointegration Tests." 
932-        Queen's University, Dept of Economics, Working Papers.  Available at 
933-        http://ideas.repec.org/p/qed/wpaper/1227.html 
931+     .. [* ] MacKinnon, J.G. 2010. "Critical Values for Cointegration Tests." 
932+             Queen's University, Dept of Economics, Working Papers.  Available at 
933+             http://ideas.repec.org/p/qed/wpaper/1227.html 
934934    """ 
935935
936936    def  __init__ (self , y , lags = None , trend = 'c' , test_type = 'tau' ):
@@ -1022,8 +1022,8 @@ class KPSS(UnitRootTest):
10221022    lags : int, optional 
10231023        The number of lags to use in the Newey-West estimator of the long-run 
10241024        covariance.  If omitted or None, the number of lags is calculated 
1025-         with the data-dependent method of Hobijn et al. (1998) [2]_ . See also 
1026-         Andrews (1991) [3]_ , Newey & West (1994) [4]_ , and Schwert (1989) [5]_ . 
1025+         with the data-dependent method of Hobijn et al. (1998). See also 
1026+         Andrews (1991), Newey & West (1994), and Schwert (1989). 
10271027        Set lags=-1 to use the old method that only depends on the sample 
10281028        size, 12 * (nobs/100) ** (1/4). 
10291029    trend : {'c', 'ct'}, optional 
@@ -1047,7 +1047,7 @@ class KPSS(UnitRootTest):
10471047    Notes 
10481048    ----- 
10491049    The null hypothesis of the KPSS test is that the series is weakly 
1050-     stationary and the alternative is that it is non-stationary [1]_ . 
1050+     stationary and the alternative is that it is non-stationary. 
10511051    If the p-value is above a critical size, then the null cannot be 
10521052    rejected that there and the series appears stationary. 
10531053
@@ -1075,22 +1075,22 @@ class KPSS(UnitRootTest):
10751075
10761076    References 
10771077    ---------- 
1078-     .. [3 ] Andrews, D.W.K. (1991). "Heteroskedasticity and autocorrelation 
1079-        consistent covariance matrix estimation". Econometrica, 59: 817-858. 
1078+     .. [* ] Andrews, D.W.K. (1991). "Heteroskedasticity and autocorrelation 
1079+             consistent covariance matrix estimation". Econometrica, 59: 817-858. 
10801080
1081-     .. [2 ] Hobijn, B., Frances, B.H., & Ooms, M. (2004). Generalizations 
1082-        of the KPSS-test for stationarity. Statistica Neerlandica, 52: 483-502. 
1081+     .. [* ] Hobijn, B., Frances, B.H., & Ooms, M. (2004). Generalizations 
1082+             of the KPSS-test for stationarity. Statistica Neerlandica, 52: 483-502. 
10831083
1084-     .. [1 ] Kwiatkowski, D.; Phillips, P. C. B.; Schmidt, P.; Shin, Y. (1992). 
1085-        "Testing the null hypothesis of stationarity against the alternative of 
1086-        a unit root". Journal of Econometrics 54 (1-3), 159-178 
1084+     .. [* ] Kwiatkowski, D.; Phillips, P. C. B.; Schmidt, P.; Shin, Y. (1992). 
1085+             "Testing the null hypothesis of stationarity against the alternative of 
1086+             a unit root". Journal of Econometrics 54 (1-3), 159-178 
10871087
1088-     .. [4 ] Newey, W.K., & West, K.D. (1994). "Automatic lag selection in 
1089-        covariance matrix estimation". Review of Economic Studies, 61: 631-653. 
1088+     .. [* ] Newey, W.K., & West, K.D. (1994). "Automatic lag selection in 
1089+             covariance matrix estimation". Review of Economic Studies, 61: 631-653. 
10901090
1091-     .. [5 ] Schwert, G. W. (1989). "Tests for unit roots: A Monte Carlo 
1092-        investigation". Journal of Business and Economic Statistics, 7 (2): 
1093-        147-159. 
1091+     .. [* ] Schwert, G. W. (1989). "Tests for unit roots: A Monte Carlo 
1092+             investigation". Journal of Business and Economic Statistics, 7 (2): 
1093+             147-159. 
10941094    """ 
10951095
10961096    def  __init__ (self , y , lags = None , trend = 'c' ):
@@ -1206,8 +1206,8 @@ class ZivotAndrews(UnitRootTest):
12061206    ----- 
12071207    H0 = unit root with a single structural break 
12081208
1209-     Algorithm follows Baum (2004/2015) [1]_  approximation to original 
1210-     Zivot-Andrews [2]_  method. Rather than performing an autolag regression at 
1209+     Algorithm follows Baum (2004/2015) approximation to original 
1210+     Zivot-Andrews method. Rather than performing an autolag regression at 
12111211    each candidate break period (as per the original paper), a single 
12121212    autolag regression is run up-front on the base model (constant + trend 
12131213    with no dummies) to determine the best lag length. This lag length is 
@@ -1219,17 +1219,17 @@ class ZivotAndrews(UnitRootTest):
12191219
12201220    References 
12211221    ---------- 
1222-     .. [1 ] Baum, C.F. (2004). ZANDREWS: Stata module to calculate Zivot-Andrews 
1223-        unit root test in presence of structural break," Statistical Software 
1224-        Components S437301, Boston College Department of Economics, revised 
1225-        2015. 
1222+     .. [* ] Baum, C.F. (2004). ZANDREWS: Stata module to calculate Zivot-Andrews 
1223+             unit root test in presence of structural break," Statistical Software 
1224+             Components S437301, Boston College Department of Economics, revised 
1225+             2015. 
12261226
12271227    .. [*] Schwert, G.W. (1989). Tests for unit roots: A Monte Carlo 
1228-        investigation. Journal of Business & Economic Statistics, 7: 147-159. 
1228+             investigation. Journal of Business & Economic Statistics, 7: 147-159. 
12291229
1230-     .. [2 ] Zivot, E., and Andrews, D.W.K. (1992). Further evidence on the great 
1231-        crash, the oil-price shock, and the unit-root hypothesis. Journal of 
1232-        Business & Economic Studies, 10: 251-270. 
1230+     .. [* ] Zivot, E., and Andrews, D.W.K. (1992). Further evidence on the great 
1231+             crash, the oil-price shock, and the unit-root hypothesis. Journal of 
1232+             Business & Economic Studies, 10: 251-270. 
12331233    """ 
12341234    def  __init__ (self , y , lags = None , trend = 'c' , trim = 0.15 , max_lags = None , method = 'AIC' ):
12351235        super (ZivotAndrews , self ).__init__ (y , lags , trend , ('c' , 't' , 'ct' ))
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