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diff --git a/gsl-1.9/rng/mrg.c b/gsl-1.9/rng/mrg.c
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+/* rng/mrg.c
+ * 
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000 James Theiler, Brian Gough
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include <config.h>
+#include <stdlib.h>
+#include <gsl/gsl_rng.h>
+
+/* This is a fifth-order multiple recursive generator. The sequence is,
+
+   x_n = (a_1 x_{n-1} + a_5 x_{n-5}) mod m
+
+   with a_1 = 107374182, a_2 = a_3 = a_4 = 0, a_5 = 104480 and m = 2^31-1.
+
+   We initialize the generator with x_n = s_n MOD m for n = 1..5,
+   where s_n = (69069 * s_{n-1}) mod 2^32, and s_0 = s is the
+   user-supplied seed.
+
+   NOTE: According to the paper the seeds must lie in the range [0,
+   2^31 - 2] with at least one non-zero value -- our seeding procedure
+   satisfies these constraints.
+
+   We then use 6 iterations of the generator to "warm up" the internal
+   state.
+
+   With this initialization procedure the theoretical value of
+   z_{10006} is 2064828650 for s = 1. The subscript 10006 means (1)
+   seed the generator with s = 1, (2) do the 6 warm-up iterations
+   that are part of the seeding process, (3) then do 10000 actual
+   iterations.
+
+   The period of this generator is about 2^155.
+
+   From: P. L'Ecuyer, F. Blouin, and R. Coutre, "A search for good
+   multiple recursive random number generators", ACM Transactions on
+   Modeling and Computer Simulation 3, 87-98 (1993). */
+
+static inline unsigned long int mrg_get (void *vstate);
+static double mrg_get_double (void *vstate);
+static void mrg_set (void *state, unsigned long int s);
+
+static const long int m = 2147483647;
+static const long int a1 = 107374182, q1 = 20, r1 = 7;
+static const long int a5 = 104480, q5 = 20554, r5 = 1727;
+
+typedef struct
+  {
+    long int x1, x2, x3, x4, x5;
+  }
+mrg_state_t;
+
+static inline unsigned long int
+mrg_get (void *vstate)
+{
+  mrg_state_t *state = (mrg_state_t *) vstate;
+
+  long int p1, h1, p5, h5;
+
+  h5 = state->x5 / q5;
+  p5 = a5 * (state->x5 - h5 * q5) - h5 * r5;
+  if (p5 > 0)
+    p5 -= m;
+
+  h1 = state->x1 / q1;
+  p1 = a1 * (state->x1 - h1 * q1) - h1 * r1;
+  if (p1 < 0)
+    p1 += m;
+
+  state->x5 = state->x4;
+  state->x4 = state->x3;
+  state->x3 = state->x2;
+  state->x2 = state->x1;
+
+  state->x1 = p1 + p5;
+
+  if (state->x1 < 0)
+    state->x1 += m;
+
+  return state->x1;
+}
+
+static double
+mrg_get_double (void *vstate)
+{
+  return mrg_get (vstate) / 2147483647.0 ;
+}
+
+
+static void
+mrg_set (void *vstate, unsigned long int s)
+{
+  /* An entirely adhoc way of seeding! This does **not** come from
+     L'Ecuyer et al */
+
+  mrg_state_t *state = (mrg_state_t *) vstate;
+
+  if (s == 0)
+    s = 1;      /* default seed is 1 */
+
+#define LCG(n) ((69069 * n) & 0xffffffffUL)
+  s = LCG (s);
+  state->x1 = s % m;
+  s = LCG (s);
+  state->x2 = s % m;
+  s = LCG (s);
+  state->x3 = s % m;
+  s = LCG (s);
+  state->x4 = s % m;
+  s = LCG (s);
+  state->x5 = s % m;
+
+  /* "warm it up" with at least 5 calls to go through
+     all the x values */
+
+  mrg_get (state);
+  mrg_get (state);
+  mrg_get (state);
+  mrg_get (state);
+  mrg_get (state);
+  mrg_get (state);
+
+  return;
+}
+
+static const gsl_rng_type mrg_type =
+{"mrg",                         /* name */
+ 2147483646,                    /* RAND_MAX */
+ 0,                             /* RAND_MIN */
+ sizeof (mrg_state_t),
+ &mrg_set,
+ &mrg_get,
+ &mrg_get_double};
+
+const gsl_rng_type *gsl_rng_mrg = &mrg_type;