@article{JEDP_2000____A9_0,
     author = {Kay, Bernard},
     title = {Application of linear hyperbolic {PDE} to linear quantum fields in curved spacetimes : especially black holes, time machines and a new semi-local vacuum concept},
     journal = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {9},
     pages = {1--19},
     publisher = {Universit\'e de Nantes},
     year = {2000},
     mrnumber = {2001h:83042},
     zbl = {01808699},
     language = {en},
     url = {http://archive.numdam.org/item/JEDP_2000____A9_0/}
}