diff --git a/src/citeme.cpp b/src/citeme.cpp
index 0ffdf02ddb..b8a1d656d9 100644
--- a/src/citeme.cpp
+++ b/src/citeme.cpp
@@ -77,7 +77,7 @@ void CiteMe::add(const std::string &reference)
 {
   if (comm->me != 0) return;
 
-  unsigned int crc = get_hash(reference);
+  std::size_t crc = get_hash(reference);
   if (cs->find(crc) != cs->end()) return;
   cs->insert(crc);
 
diff --git a/src/citeme.h b/src/citeme.h
index 10fa055b2c..df87f1f9e5 100644
--- a/src/citeme.h
+++ b/src/citeme.h
@@ -34,7 +34,7 @@ class CiteMe : protected Pointers {
   int logfile_flag;            // determine whether verbose or terse output
   std::string scrbuffer;       // output buffer for screen
   std::string logbuffer;       // output buffer for logfile
-  typedef std::set<unsigned int> citeset;
+  typedef std::set<std::size_t> citeset;
   citeset *cs;                 // registered set of publications
 };
 }