@phdthesis{BJHTUP11_1980__0091__P0_0,
     author = {Guyon, Xavier},
     title = {Semi-martingales \`a indice dans $\mathbb{R}^2$},
     series = {Th\`eses d'Orsay},
     publisher = {Universit\'e de Paris-Sud Centre d'Orsay},
     number = {91},
     year = {1980},
     language = {fr},
     url = {http://www.numdam.org/item/BJHTUP11_1980__0091__P0_0/}
}