McLachlan, R. I., &; Offen, C. (2018). Hamiltonian boundary value problems, conformal symplectic symmetries, and conjugate loci. New Zealand Journal of Mathematics, 48, 83–99.https://doi.org/10.53733/34  
LibreCat: /record/19943
DOI: 10.53733/34 
arXiv: 1804.07479