diff --git a/chrono/datetime.h b/chrono/datetime.h
index 298c6b1..ead4a25 100644
--- a/chrono/datetime.h
+++ b/chrono/datetime.h
@@ -536,6 +536,7 @@ inline DateTime &DateTime::operator-=(const TimeSpan &timeSpan)
 } // namespace CppUtilities
 
 namespace std {
+/// \brief Computes the hash for the CppUtilities::DateTime instance.
 template <> struct hash<CppUtilities::DateTime> {
     inline size_t operator()(const CppUtilities::DateTime &dateTime) const
     {
diff --git a/chrono/timespan.h b/chrono/timespan.h
index 6726287..07273db 100644
--- a/chrono/timespan.h
+++ b/chrono/timespan.h
@@ -422,6 +422,7 @@ constexpr inline bool TimeSpan::isInfinity() const
 } // namespace CppUtilities
 
 namespace std {
+/// \brief Computes the hash for the CppUtilities::TimeSpan instance.
 template <> struct hash<CppUtilities::TimeSpan> {
     inline size_t operator()(const CppUtilities::TimeSpan &timeSpan) const
     {