diff git a/demos/polynomial_fit.py b/demos/polynomial_fit.py
index 68a6c677dd6baaeb8cb456da5cd219a63ee6da36..cf5f776d8f09a06878fb733e0c3428d00824dda5 100644
 a/demos/polynomial_fit.py
+++ b/demos/polynomial_fit.py
@@ 44,7 +44,8 @@ def polynomial(coefficients, sampling_points):
class PolynomialResponse(ift.LinearOperator):
 """Calculates values of a polynomial parameterized by input at sampling points.
+ """Calculates values of a polynomial parameterized by input at sampling
+ points.
Parameters

diff git a/nifty5/extra.py b/nifty5/extra.py
index fb83ba415de4047428c3ed53648d78cf02edaa37..387b41856e02d44b9d11200d030b93d309c259e1 100644
 a/nifty5/extra.py
+++ b/nifty5/extra.py
@@ 171,4 +171,3 @@ def check_jacobian_consistency(op, loc, tol=1e8, ntries=100):
else:
raise ValueError("gradient and value seem inconsistent")
loc = locnext

diff git a/nifty5/library/light_cone_operator.py b/nifty5/library/light_cone_operator.py
index 4c28201e08d3014e400e272b50aecff200c9bb0e..c680d5f0c14086e549636a6732d1bc441b0839fe 100644
 a/nifty5/library/light_cone_operator.py
+++ b/nifty5/library/light_cone_operator.py
@@ 97,24 +97,24 @@ def _cone_arrays(c, domain, sigx, want_gradient):
class LightConeOperator(Operator):
'''Constructs a Light cone from a set of lightspeed parameters.

+
The resulting cone is defined as follows

+
.. math::
\\exp \\left( \\frac{1}{2} \\Re \\left( \\Delta \\right)^2 \\right)

+
with

+
.. math::
\\Delta = \\sqrt{ \\left(t^2  \\frac{x^\\dagger C^{1} x}
{\\sigma_x^2} \\right)}

+
where t and x are the coordinates of the target space. Note that axis zero
of the space is interpreted as the time axis. C denotes the input
paramters of the operator and parametrizes the shape of the cone.
sigx is the width of the asymptotic Gaussian in x necessary for
discretization.

+
Parameters

domain : Domain, tuple of Domain or DomainTuple
diff git a/nifty5/operators/exp_transform.py b/nifty5/operators/exp_transform.py
index 5028ee14f730732f5b00df5fca6819c7109d579b..47e0c7c97a6d629f7cd6cd05e9bb6303dd098200 100644
 a/nifty5/operators/exp_transform.py
+++ b/nifty5/operators/exp_transform.py
@@ 31,8 +31,8 @@ class ExpTransform(LinearOperator):
This operator creates a logspace subject to the degrees of freedom and
and its targetdomain.
 Then it transforms between this logspace and its target, which is defined in
 normal units.
+ Then it transforms between this logspace and its target, which is defined
+ in normal units.
FIXME Write something on t_0 of domain space