Jacobson, Ted; Smolin, Lee (1987). «The left-handed spin connection as a variable for canonical gravity». Physics Letters B (Elsevier BV) 196 (1): 39-42. ISSN0370-2693. doi:10.1016/0370-2693(87)91672-8.
Jacobson, T; Smolin, L (1 de abril de 1988). «Covariant action for Ashtekar's form of canonical gravity». Classical and Quantum Gravity (IOP Publishing) 5 (4): 583-594. ISSN0264-9381. doi:10.1088/0264-9381/5/4/006.
Goldberg, J. N. (15 de abril de 1988). «Triad approach to the Hamiltonian of general relativity». Physical Review D (American Physical Society (APS)) 37 (8): 2116-2120. ISSN0556-2821. doi:10.1103/physrevd.37.2116.
Henneaux, M.; Nelson, J. E.; Schomblond, C. (15 de enero de 1989). «Derivation of Ashtekar variables from tetrad gravity». Physical Review D (American Physical Society (APS)) 39 (2): 434-437. ISSN0556-2821. doi:10.1103/physrevd.39.434.
Jacobson, Ted; Smolin, Lee (1987). «The left-handed spin connection as a variable for canonical gravity». Physics Letters B (Elsevier BV) 196 (1): 39-42. ISSN0370-2693. doi:10.1016/0370-2693(87)91672-8.
Jacobson, T; Smolin, L (1 de abril de 1988). «Covariant action for Ashtekar's form of canonical gravity». Classical and Quantum Gravity (IOP Publishing) 5 (4): 583-594. ISSN0264-9381. doi:10.1088/0264-9381/5/4/006.
Goldberg, J. N. (15 de abril de 1988). «Triad approach to the Hamiltonian of general relativity». Physical Review D (American Physical Society (APS)) 37 (8): 2116-2120. ISSN0556-2821. doi:10.1103/physrevd.37.2116.
Henneaux, M.; Nelson, J. E.; Schomblond, C. (15 de enero de 1989). «Derivation of Ashtekar variables from tetrad gravity». Physical Review D (American Physical Society (APS)) 39 (2): 434-437. ISSN0556-2821. doi:10.1103/physrevd.39.434.