V. Ayala, E. Cruz, L. Laura, and W. Kliemann. Controllability properties of bilinear systems in dimension 2. Journal of Mathematics and Computer Science, volume 16, pages 554-575, 2016. V. Ayala, W. Kliemann, and F. Vera. Isochronous sets of invariant control systems. Systems \& Control Letters, Elsevier, volume 60, issue 12, pages 937-942, 2011. V. Ayala, E. Cruz, and W. Kliemann. Controllability of bilinear systems on the projective space. Computer and Mathematics with Applications, 2009.