SUBROUTINE SLAS2U(AJJ, AJK, AKK, SMIN, SMAX)

      IMPLICIT NONE

      REAL AJJ,AJK,AKK,SMIN,SMAX
      REAL ALPHA, BETA, THETA1, THETA2
      REAL T, R1, R2
      REAL CSL,SNL,CSR,SNR
      REAL C0, S0, TMP1, TMP2, TMP3, TMP4
      REAL ONE, ZERO, HALF, TWO, CONST
      PARAMETER (ONE = 1.0E0, ZERO = 0.0E0, HALF = 0.5E0, TWO = 2.0E0)
      EXTERNAL SFMA0
      REAL SFMA0

      IF (AJJ .EQ. ZERO .AND. AJK .EQ. ZERO .AND. AKK .EQ. ZERO) THEN

         SMIN = ZERO
         SMAX = ZERO

      ELSE

         TMP2 = AJJ
         TMP3 = AJK
         TMP4 = AKK

         ALPHA = ATAN ( DBLE(TMP3 / ( TMP2 - TMP4 ) ) )
         BETA = ATAN ( DBLE(TMP3 / ( TMP2 + TMP4 ) ) )
         THETA1 = (ALPHA + BETA) * HALF
         THETA2 = (ALPHA - BETA) * HALF

         CSL = COS (DBLE(THETA1))
         SNL = SIN (DBLE(THETA1))
         CSR = COS (DBLE(THETA2))
         SNR = SIN (DBLE(THETA2))

         T = CSL + CSR
         R1 = SNL / T
         R2 = -SNR / T

         SMAX = ABS(SFMA0(TMP3,R1,TMP2))
         SMIN = ABS(SFMA0(TMP3,R2,TMP4))

         IF (SMAX .LT. SMIN) THEN
            T = SMAX
            SMAX = SMIN
            SMIN = T
         ENDIF

      ENDIF

      RETURN

      END SUBROUTINE SLAS2U