@article{JEDP_1982____A7_0,
     author = {Fefferman, Charles and Phong, D. H.},
     title = {Lower bounds for {Schr\"odinger} equations},
     journal = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {7},
     pages = {1--7},
     publisher = {Ecole polytechnique},
     year = {1982},
     zbl = {0492.35057},
     language = {en},
     url = {http://www.numdam.org/item/JEDP_1982____A7_0/}
}