diff --git a/SRC/dgees.f b/SRC/dgees.f
index 23f2954e3..5e4e7c245 100644
--- a/SRC/dgees.f
+++ b/SRC/dgees.f
@@ -227,8 +227,12 @@
      $                   WR( * )
 *     ..
 *     .. Function Arguments ..
-      LOGICAL            SELECT
-      EXTERNAL           SELECT
+      INTERFACE
+        LOGICAL FUNCTION SELECT_PROC_TYPE(WR, WI) BIND(C)
+          DOUBLE PRECISION WR, WI
+        END FUNCTION SELECT_PROC_TYPE
+      END INTERFACE
+      PROCEDURE(SELECT_PROC_TYPE) :: SELECT
 *     ..
 *
 *  =====================================================================
diff --git a/SRC/dgeesx.f b/SRC/dgeesx.f
index 93f119ea9..1e99dda92 100644
--- a/SRC/dgeesx.f
+++ b/SRC/dgeesx.f
@@ -294,8 +294,12 @@
      $                   WR( * )
 *     ..
 *     .. Function Arguments ..
-      LOGICAL            SELECT
-      EXTERNAL           SELECT
+      INTERFACE
+        LOGICAL FUNCTION SELECT_PROC_TYPE(WR, WI) BIND(C)
+          DOUBLE PRECISION WR, WI
+        END FUNCTION SELECT_PROC_TYPE
+      END INTERFACE
+      PROCEDURE(SELECT_PROC_TYPE) :: SELECT
 *     ..
 *
 *  =====================================================================
diff --git a/SRC/dgges.f b/SRC/dgges.f
index b700860f6..77b3b4dca 100644
--- a/SRC/dgges.f
+++ b/SRC/dgges.f
@@ -297,8 +297,12 @@
      $                   VSR( LDVSR, * ), WORK( * )
 *     ..
 *     .. Function Arguments ..
-      LOGICAL            SELCTG
-      EXTERNAL           SELCTG
+      INTERFACE
+        LOGICAL FUNCTION SELCTG_PROC_TYPE(ALPHAR, ALPHAI, BETA) BIND(C)
+          DOUBLE PRECISION ALPHAR, ALPHAI, BETA
+        END FUNCTION SELCTG_PROC_TYPE
+      END INTERFACE
+      PROCEDURE(SELCTG_PROC_TYPE) :: SELCTG
 *     ..
 *
 *  =====================================================================
diff --git a/SRC/dgges3.f b/SRC/dgges3.f
index 5ea3f5dbd..0d2cf4461 100644
--- a/SRC/dgges3.f
+++ b/SRC/dgges3.f
@@ -296,8 +296,12 @@
      $                   VSR( LDVSR, * ), WORK( * )
 *     ..
 *     .. Function Arguments ..
-      LOGICAL            SELCTG
-      EXTERNAL           SELCTG
+      INTERFACE
+        LOGICAL FUNCTION SELCTG_PROC_TYPE(ALPHAR, ALPHAI, BETA) BIND(C)
+          DOUBLE PRECISION ALPHAR, ALPHAI, BETA
+        END FUNCTION SELCTG_PROC_TYPE
+      END INTERFACE
+      PROCEDURE(SELCTG_PROC_TYPE) :: SELCTG
 *     ..
 *
 *  =====================================================================
diff --git a/SRC/dggesx.f b/SRC/dggesx.f
index c716af4c9..3d649eed7 100644
--- a/SRC/dggesx.f
+++ b/SRC/dggesx.f
@@ -381,8 +381,12 @@
      $                   WORK( * )
 *     ..
 *     .. Function Arguments ..
-      LOGICAL            SELCTG
-      EXTERNAL           SELCTG
+      INTERFACE
+        LOGICAL FUNCTION SELCTG_PROC_TYPE(ALPHAR, ALPHAI, BETA) BIND(C)
+          DOUBLE PRECISION ALPHAR, ALPHAI, BETA
+        END FUNCTION SELCTG_PROC_TYPE
+      END INTERFACE
+      PROCEDURE(SELCTG_PROC_TYPE) :: SELCTG
 *     ..
 *
 *  =====================================================================