diff --git a/pina/condition/data_condition.py b/pina/condition/data_condition.py
index d0d0702..2d776a2 100644
--- a/pina/condition/data_condition.py
+++ b/pina/condition/data_condition.py
@@ -68,10 +68,12 @@ class DataCondition(ConditionInterface):
         :type conditional_variables: torch.Tensor or LabelTensor
 
         .. note::
-            If either `input` is composed by a list of :class:`~pina.graph.Graph`
-            or :class:`~torch_geometric.data.Data` objects, all elements must
-            have the same structure (keys and data types)
+            If either `input` is composed by a list of
+            :class:`~pina.graph.Graph` or :class:`~torch_geometric.data.Data`
+            objects, all elements must have the same structure (keys and data
+            types)
         """
+
         super().__init__()
         self.input = input
         self.conditional_variables = conditional_variables
diff --git a/pina/graph.py b/pina/graph.py
index c6f5335..45cd0e6 100644
--- a/pina/graph.py
+++ b/pina/graph.py
@@ -20,8 +20,8 @@ class Graph(Data):
         **kwargs,
     ):
         """
-        Create a new instance of the :class:`~pina.graph.Graph` class by checking
-        the consistency of the input data and storing the attributes.
+        Create a new instance of the :class:`~pina.graph.Graph` class by
+        checking the consistency of the input data and storing the attributes.
 
         :param kwargs: Parameters used to initialize the
             :class:`~pina.graph.Graph` object.
@@ -339,8 +339,8 @@ class KNNGraph(GraphBuilder):
 
     def __new__(cls, pos, neighbours, **kwargs):
         """
-        Extends the :class:`~pina.graph.GraphBuilder` class to compute edge_index
-        based on a K-nearest neighbors algorithm.
+        Extends the :class:`~pina.graph.GraphBuilder` class to compute
+        edge_index based on a K-nearest neighbors algorithm.
 
         :param pos: A tensor of shape (N, D) representing the positions of N
             points in D-dimensional space.
diff --git a/pina/label_tensor.py b/pina/label_tensor.py
index 48e7f62..4647ee5 100644
--- a/pina/label_tensor.py
+++ b/pina/label_tensor.py
@@ -275,7 +275,8 @@ class LabelTensor(torch.Tensor):
 
     def __str__(self):
         """
-        The string representation of the :class:`~pina.label_tensor.LabelTensor`.
+        The string representation of the
+        :class:`~pina.label_tensor.LabelTensor`.
 
         :return: String representation of the
             :class:`~pina.label_tensor.LabelTensor` instance.
@@ -295,8 +296,8 @@ class LabelTensor(torch.Tensor):
         Concatenate a list of tensors along a specified dimension. For more
         details, see :meth:`torch.cat`.
 
-        :param list[LabelTensor] tensors: :class:`~pina.label_tensor.LabelTensor`
-            instances to concatenate
+        :param list[LabelTensor] tensors:
+            :class:`~pina.label_tensor.LabelTensor` instances to concatenate
         :param int dim: dimensions on which you want to perform the operation
             (default is 0)
         :return: A new :class:`LabelTensor' instance obtained by concatenating
@@ -472,8 +473,8 @@ class LabelTensor(torch.Tensor):
         Stack tensors vertically. For more details, see :meth:`torch.vstack`.
 
         :param list of LabelTensor label_tensors: The
-            :class:`~pina.label_tensor.LabelTensor` instances to stack. They need
-            to have equal labels.
+            :class:`~pina.label_tensor.LabelTensor` instances to stack. They
+            need to have equal labels.
         :return: A new :class:`~pina.label_tensor.LabelTensor` instance obtained
             by stacking the input tensors vertically.
         :rtype: LabelTensor