diff --git a/src/lib.rs b/src/lib.rs
index 69fb2ca..7b88324 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -393,4 +393,23 @@ mod test {
     fn test_ahasher_construction() {
         let _ = AHasher::new_with_keys(1234, 5678);
     }
+
+    #[test]
+    fn test_specialize_reference_hash() {
+        let hasher_build = RandomState::with_seeds(0, 0, 0, 0);
+        let h1 = hasher_build.hash_one(1u64);
+        let h2 = hasher_build.hash_one(&1u64);
+
+        assert_eq!(h1, h2);
+
+        let h1 = u64::get_hash(&1_u64, &hasher_build);
+        let h2 = <&u64>::get_hash(&&1_u64, &hasher_build);
+
+        assert_eq!(h1, h2);
+
+        let h1 = hasher_build.hash_one(1u128);
+        let h2 = hasher_build.hash_one(&1u128);
+
+        assert_eq!(h1, h2);
+    }
 }
diff --git a/src/specialize.rs b/src/specialize.rs
index 05d335b..acdf7d1 100644
--- a/src/specialize.rs
+++ b/src/specialize.rs
@@ -47,7 +47,7 @@ where
     }
 }
 
-macro_rules! call_hasher_impl {
+macro_rules! call_hasher_impl_u64 {
     ($typ:ty) => {
         #[cfg(feature = "specialize")]
         impl CallHasher for $typ {
@@ -58,46 +58,43 @@ macro_rules! call_hasher_impl {
         }
     };
 }
-call_hasher_impl!(u8);
-call_hasher_impl!(u16);
-call_hasher_impl!(u32);
-call_hasher_impl!(u64);
-call_hasher_impl!(i8);
-call_hasher_impl!(i16);
-call_hasher_impl!(i32);
-call_hasher_impl!(i64);
-
-#[cfg(feature = "specialize")]
-impl CallHasher for u128 {
-    #[inline]
-    fn get_hash<H: Hash + ?Sized, B: BuildHasher>(value: &H, build_hasher: &B) -> u64 {
-        build_hasher.hash_as_fixed_length(value)
-    }
-}
-
-#[cfg(feature = "specialize")]
-impl CallHasher for i128 {
-    #[inline]
-    fn get_hash<H: Hash + ?Sized, B: BuildHasher>(value: &H, build_hasher: &B) -> u64 {
-        build_hasher.hash_as_fixed_length(value)
-    }
-}
-
-#[cfg(feature = "specialize")]
-impl CallHasher for usize {
-    #[inline]
-    fn get_hash<H: Hash + ?Sized, B: BuildHasher>(value: &H, build_hasher: &B) -> u64 {
-        build_hasher.hash_as_fixed_length(value)
-    }
+call_hasher_impl_u64!(u8);
+call_hasher_impl_u64!(u16);
+call_hasher_impl_u64!(u32);
+call_hasher_impl_u64!(u64);
+call_hasher_impl_u64!(i8);
+call_hasher_impl_u64!(i16);
+call_hasher_impl_u64!(i32);
+call_hasher_impl_u64!(i64);
+call_hasher_impl_u64!(&u8);
+call_hasher_impl_u64!(&u16);
+call_hasher_impl_u64!(&u32);
+call_hasher_impl_u64!(&u64);
+call_hasher_impl_u64!(&i8);
+call_hasher_impl_u64!(&i16);
+call_hasher_impl_u64!(&i32);
+call_hasher_impl_u64!(&i64);
+
+macro_rules! call_hasher_impl_fixed_length{
+    ($typ:ty) => {
+        #[cfg(feature = "specialize")]
+        impl CallHasher for $typ {
+            #[inline]
+            fn get_hash<H: Hash + ?Sized, B: BuildHasher>(value: &H, build_hasher: &B) -> u64 {
+                build_hasher.hash_as_fixed_length(value)
+            }
+        }
+    };
 }
 
-#[cfg(feature = "specialize")]
-impl CallHasher for isize {
-    #[inline]
-    fn get_hash<H: Hash + ?Sized, B: BuildHasher>(value: &H, build_hasher: &B) -> u64 {
-        build_hasher.hash_as_fixed_length(value)
-    }
-}
+call_hasher_impl_fixed_length!(u128);
+call_hasher_impl_fixed_length!(i128);
+call_hasher_impl_fixed_length!(usize);
+call_hasher_impl_fixed_length!(isize);
+call_hasher_impl_fixed_length!(&u128);
+call_hasher_impl_fixed_length!(&i128);
+call_hasher_impl_fixed_length!(&usize);
+call_hasher_impl_fixed_length!(&isize);
 
 #[cfg(feature = "specialize")]
 impl CallHasher for [u8] {