diff --git a/openmc/material.py b/openmc/material.py
index 419e310460..b0d5cb2229 100644
--- a/openmc/material.py
+++ b/openmc/material.py
@@ -58,9 +58,10 @@ class Material(IDManagerMixin):
         applies in the case of a multi-group calculation.
     depletable : bool
         Indicate whether the material is depletable.
-    nuclides : list of tuple
-        List in which each item is a 3-tuple consisting of a nuclide string, the
-        percent density, and the percent type ('ao' or 'wo').
+    nuclides : list of namedtuple
+        List in which each item is a namedtuple consisting of a nuclide string,
+        the percent density, and the percent type ('ao' or 'wo'). The namedtuple
+        has field names ``name``, ``percent``, and ``percent_type``.
     isotropic : list of str
         Nuclides for which elastic scattering should be treated as though it
         were isotropic in the laboratory system.
diff --git a/openmc/mgxs_library.py b/openmc/mgxs_library.py
index aae2d1b456..179885260c 100644
--- a/openmc/mgxs_library.py
+++ b/openmc/mgxs_library.py
@@ -57,7 +57,7 @@ class XSdata:
         Name of the mgxs data set.
     energy_groups : openmc.mgxs.EnergyGroups
         Energy group structure
-    representation : {'isotropic', REPRESENTATION_ANGLE}, optional
+    representation : {'isotropic', 'angle'}, optional
         Method used in generating the MGXS (isotropic or angle-dependent flux
         weighting). Defaults to 'isotropic'
     temperatures : Iterable of float
@@ -88,7 +88,7 @@ class XSdata:
         Either the Legendre order, number of bins, or number of points used to
         describe the angular distribution associated with each group-to-group
         transfer probability.
-    representation : {'isotropic', REPRESENTATION_ANGLE}
+    representation : {'isotropic', 'angle'}
         Method used in generating the MGXS (isotropic or angle-dependent flux
         weighting).
     num_azimuthal : int
diff --git a/openmc/tallies.py b/openmc/tallies.py
index 11f2fb0676..a8687bb373 100644
--- a/openmc/tallies.py
+++ b/openmc/tallies.py
@@ -129,17 +129,17 @@ class Tally(IDManagerMixin):
 
     def __repr__(self):
         parts = ['Tally']
-        parts.append('{: <16}=\t{}'.format('\tID', self.id))
-        parts.append('{: <16}=\t{}'.format('\tName', self.name))
+        parts.append('{: <15}=\t{}'.format('ID', self.id))
+        parts.append('{: <15}=\t{}'.format('Name', self.name))
         if self.derivative is not None:
-            parts.append('{: <16}=\t{}'.format('\tDerivative ID', self.derivative.id))
+            parts.append('{: <15}=\t{}'.format('Derivative ID', self.derivative.id))
         filters = ', '.join(type(f).__name__ for f in self.filters)
-        parts.append('{: <16}=\t{}'.format('\tFilters', filters))
+        parts.append('{: <15}=\t{}'.format('Filters', filters))
         nuclides = ' '.join(str(nuclide) for nuclide in self.nuclides)
-        parts.append('{: <16}=\t'.format('\tNuclides', nuclides))
-        parts.append('{: <16}=\t{}\n'.format('\tScores', self.scores))
-        parts.append('{: <16}=\t{}\n'.format('\tEstimator', self.estimator))
-        return '\n'.join(parts)
+        parts.append('{: <15}=\t{}'.format('Nuclides', nuclides))
+        parts.append('{: <15}=\t{}'.format('Scores', self.scores))
+        parts.append('{: <15}=\t{}'.format('Estimator', self.estimator))
+        return '\n\t'.join(parts)
 
     @property
     def name(self):