Craig, Norman C.; Groner, Peter; McKean, Donald C. Equilibrium Structures for Butadiene and Ethylene: Compelling Evidence for Π-Electron Delocalization in Butadiene. The Journal of Physical Chemistry A. 2006-06-01, 110 (23): 7461–7469. Bibcode:2006JPCA..110.7461C. ISSN 1089-5639. PMID 16759136. doi:10.1021/jp060695b.
Craig, Norman C.; Groner, Peter; McKean, Donald C. Equilibrium Structures for Butadiene and Ethylene: Compelling Evidence for Π-Electron Delocalization in Butadiene. The Journal of Physical Chemistry A. 2006-06-01, 110 (23): 7461–7469. Bibcode:2006JPCA..110.7461C. ISSN 1089-5639. PMID 16759136. doi:10.1021/jp060695b.
Craig, Norman C.; Groner, Peter; McKean, Donald C. Equilibrium Structures for Butadiene and Ethylene: Compelling Evidence for Π-Electron Delocalization in Butadiene. The Journal of Physical Chemistry A. 2006-06-01, 110 (23): 7461–7469. Bibcode:2006JPCA..110.7461C. ISSN 1089-5639. PMID 16759136. doi:10.1021/jp060695b.
Craig, Norman C.; Groner, Peter; McKean, Donald C. Equilibrium Structures for Butadiene and Ethylene: Compelling Evidence for Π-Electron Delocalization in Butadiene. The Journal of Physical Chemistry A. 2006-06-01, 110 (23): 7461–7469. Bibcode:2006JPCA..110.7461C. ISSN 1089-5639. PMID 16759136. doi:10.1021/jp060695b.