@incollection{AST_1987__147-148__325_0,
     author = {Pintz, J.},
     title = {An effective disproof of the {Mertens} conjecture},
     booktitle = {Journ\'ees arithm\'etiques de Besan\c{c}on},
     series = {Ast\'erisque},
     pages = {325--333},
     publisher = {Soci\'et\'e math\'ematique de France},
     number = {147-148},
     year = {1987},
     zbl = {0623.10031},
     language = {en},
     url = {http://www.numdam.org/item/AST_1987__147-148__325_0/}
}