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that I have been able to find. Please alert me if I have missed some related work or citations.

Westbury BW

R-matrices and the magic square
J PHYS A-MATH GEN 36 (7): 1947-1959 FEB 21 2003

Maru N, Kitakado S

Negative-dimensional group extrapolation and dualities in N=1 supersymmetric gauge theories
MOD PHYS LETT A 12 (10): 691-696 MAR 28 1997

BURDIK C, NAVRATIL O, THOMA M

THE REALIZATIONS OF THE LIE ALGEBRA-G(2)
CZECH J PHYS 43 (7): 697-703 JUL 1993

OLSHANETSKII MA, ROGOV VBK

ADJOINT REPRESENTATIONS OF EXCEPTIONAL LIE-ALGEBRAS
THEOR MATH PHYS+ 72 (1): 679-685 JUL 1987