diff --git a/ostap/fitting/dataset.py b/ostap/fitting/dataset.py
index 638b5c46..77438979 100644
--- a/ostap/fitting/dataset.py
+++ b/ostap/fitting/dataset.py
@@ -8,7 +8,7 @@
 #  @author Vanya BELYAEV Ivan.Belyaev@itep.ru
 #  @date   2011-06-07
 # =============================================================================
-"""Module with decoration for RooAbsData and related RooFit classes
+""" Module with decoration for RooAbsData and related RooFit classes
 - see RooAbsData 
 - see RooDataSet 
 """
@@ -52,7 +52,7 @@
 if '__main__' ==  __name__ : logger = getLogger( 'ostap.fitting.dataset' )
 else                       : logger = getLogger( __name__ )
 # =============================================================================
-logger.debug( 'Some useful decorations for RooAbsData object')
+logger.debug ( 'Some useful decorations for RooAbsData object')
 # =============================================================================
 from ostap.logger.colorized import allright,  attention
 _new_methods_ = []
diff --git a/ostap/fitting/signals.py b/ostap/fitting/signals.py
index c543c328..82e7112b 100755
--- a/ostap/fitting/signals.py
+++ b/ostap/fitting/signals.py
@@ -174,7 +174,7 @@
 #  @author Vanya BELYAEV Ivan.Belyaeve@itep.ru
 #  @date 2011-07-25
 class Gauss_pdf(PEAK) :
-    """Trivial Gaussian function:
+    """ Trivial Gaussian function:
     http://en.wikipedia.org/wiki/Normal_distribution
     """
     def __init__ ( self               ,
@@ -237,7 +237,7 @@ def __init__ ( self               ,
 #  @author Vanya BELYAEV Ivan.Belyaev@itep.ru
 #  @date 2011-07-25
 class CrystalBall_pdf(PEAK) :
-    """Crystal Ball function
+    """ Crystal Ball function
     http://en.wikipedia.org/wiki/Crystal_Ball_function
     
     - T. Skwarnicki,
@@ -353,7 +353,7 @@ def nL ( self, value ) :
 #  @author Vanya BELYAEV Ivan.Belyaev@itep.ru
 #  @date 2011-07-25
 class CrystalBallRS_pdf(PEAK) :
-    """Right-side CrystalBall    
+    """ Right-side CrystalBall    
     """
     def __init__ ( self              ,
                    name              ,
@@ -448,7 +448,7 @@ def nR ( self, value ) :
 #  @author Vanya BELYAEV Ivan.Belyaev@itep.ru
 #  @date 2011-07-25
 class CB2_pdf(PEAK) :
-    """Double sided Crystal Ball function with both left and rigth sides
+    """ Double sided Crystal Ball function with both left and rigth sides
     It appears to be very powerful and is used for many LHCb papers to describe
     B-hadron mass signals, especially for B->J/psi X final states 
     
@@ -586,7 +586,7 @@ def alphaR ( self, value ) :
 #  @author Vanya BELYAEV Ivan.Belyaeve@itep.ru
 #  @date 2011-07-25
 class Needham_pdf(PEAK) :
-    """Needham function: specific parameterisation of Crystal Ball function with
+    """ Needham function: specific parameterisation of Crystal Ball function with
     - n = 1 
     - alpha(sigma) = a_0 + sigma*(a_1+sigma*a_2)
     
@@ -690,7 +690,7 @@ def a2 ( self, value ) :
 #  @author Vanya BELYAEV Ivan.Belyaev@itep.ru
 #  @date 2011-07-25
 class Apollonios_pdf(PEAK) :
-    """Apollonios function
+    """ Apollonios function
     http://arxiv.org/abs/1312.5000
     
     The function is proposed by Diego Martinez Santos 
@@ -804,7 +804,7 @@ def b ( self, value ) :
 #  @author Vanya BELYAEV Ivan.Belyaev@itep.ru
 #  @date 2014-08-20
 class Apollonios2_pdf(PEAK) :
-    """Bifurcated Apollonios:
+    """ Bifurcated Apollonios:
     Gaussian with exponential (asymmetrical) tails
     
     f(x; mu, sigma_l, sigma_r, beta) ~ exp( |beta|(|\beta| - sqrt( beta^2+( delta x)^2 ))      
diff --git a/source/include/Ostap/Peaks.h b/source/include/Ostap/Peaks.h
index f5519161..244278b5 100644
--- a/source/include/Ostap/Peaks.h
+++ b/source/include/Ostap/Peaks.h
@@ -1169,10 +1169,10 @@ namespace Ostap
      *  \f[ f(x;\alpha,n,x_0,\sigma) = \frac{1}{ \sqrt{2\pi\sigma^2} } \left\{
      *  \begin{array}{ll}
      *  \mathrm{e}^{-\frac{1}{2}\left(\frac{x-x_0}{\sigma}\right)^2}
-     *  & \text{for}~\frac{x-x_0}\ge-\alpha\sigma \\
-     *  \mathrm{- \frac{\alpha^2}{2}} \times
+     *  & \text{for}~\frac{x-x_0}{\sigma}\ge-\alpha \\
+     *  \mathrm{e}^{-\frac{\alpha^2}{2}} \times
      *  \left(  \frac{n+1}{ n+1 - \alpha^2 - \left|\alpha\right|\frac{x-x_0}{\sigma}}\right)^{n+1}
-     *  & \text{for}~\frac{x-x_0}\le-\alpha\sigma
+     *  & \text{for}~\frac{x-x_0}{\sigma}\le-\alpha
      *  \end{array}
      *  \right.\f]
      *