diff --git a/groestl.c b/groestl.c
index e0ea63e9e..de3784cbf 100644
--- a/groestl.c
+++ b/groestl.c
@@ -1019,21 +1019,18 @@ groestl_big_close(sph_groestl_big_context *sc,
 	groestl_big_init(sc, (unsigned)out_len << 3);
 }
 
-/* see sph_groestl.h */
 void
 groestl512_Init(void *cc)
 {
 	groestl_big_init((sph_groestl_big_context *)cc, 512);
 }
 
-/* see sph_groestl.h */
 void
 groestl512_Update(void *cc, const void *data, size_t len)
 {
 	groestl_big_core((sph_groestl_big_context *)cc, data, len);
 }
 
-/* see sph_groestl.h */
 void
 groestl512_Final(void *cc, void *dst)
 {
@@ -1046,15 +1043,7 @@ groestl512_DoubleTrunc(void *cc, void *dst)
 	char buf[64];
 
 	groestl512_Final(cc, buf);
-	groestl512_Init(cc);
 	groestl512_Update(cc, buf, sizeof(buf));
 	groestl512_Final(cc, buf);
 	memcpy(dst, buf, 32);
 }
-
-/* see sph_groestl.h */
-void
-sph_groestl512_addbits_and_close(void *cc, unsigned ub, unsigned n, void *dst)
-{
-	groestl_big_close((sph_groestl_big_context *)cc, ub, n, dst, 64);
-}
diff --git a/groestl.h b/groestl.h
index 533d8c0bb..aeabf9442 100644
--- a/groestl.h
+++ b/groestl.h
@@ -89,23 +89,7 @@ void groestl512_Update(void *cc, const void *data, size_t len);
  */
 void groestl512_Final(void *cc, void *dst);
 
-
+/* Calculate double Groestl-512 hash and truncate it to 256-bits. */
 void groestl512_DoubleTrunc(void *cc, void *dst);
 
-/**
- * Add a few additional bits (0 to 7) to the current computation, then
- * terminate it and output the result in the provided buffer, which must
- * be wide enough to accomodate the result (64 bytes). If bit number i
- * in <code>ub</code> has value 2^i, then the extra bits are those
- * numbered 7 downto 8-n (this is the big-endian convention at the byte
- * level). The context is automatically reinitialized.
- *
- * @param cc    the Groestl-512 context
- * @param ub    the extra bits
- * @param n     the number of extra bits (0 to 7)
- * @param dst   the destination buffer
- */
-void sph_groestl512_addbits_and_close(
-	void *cc, unsigned ub, unsigned n, void *dst);
-
 #endif