diff --git a/source/cell/cell.cpp b/source/cell/cell.cpp
index 667212d8..98dc1739 100644
--- a/source/cell/cell.cpp
+++ b/source/cell/cell.cpp
@@ -750,8 +750,7 @@ void cell::format(const class format new_format)
         format().d_->references -= format().d_->references > 0 ? 1 : 0;
     }
 
-    ++new_format.d_->references;
-    d_->format_ = new_format.d_;
+    d_->format_ = detail::reference(new_format.d_);
 }
 
 calendar cell::base_date() const
diff --git a/source/detail/implementations/stylesheet.hpp b/source/detail/implementations/stylesheet.hpp
index 0ec45161..9863909d 100644
--- a/source/detail/implementations/stylesheet.hpp
+++ b/source/detail/implementations/stylesheet.hpp
@@ -419,6 +419,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -431,6 +432,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -443,6 +445,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -455,6 +458,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -467,6 +471,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -483,6 +488,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -495,6 +501,7 @@ struct stylesheet
         if (pattern->references == 0)
         {
             *pattern = new_format;
+            return pattern;
         }
         return find_or_create(new_format);
     }
@@ -577,5 +584,15 @@ struct stylesheet
     std::vector<color> colors;
 };
 
+inline format_impl* reference(format_impl *impl)
+{
+    ++impl->references;
+    if (impl->references == 1)
+    {
+        impl = impl->parent->find_or_create(*impl);
+    }
+    return impl;
+}
+
 } // namespace detail
 } // namespace xlnt