@article{10_4064_aa_13_1_61_89,
     author = {P. Tur\'an},
     title = {On the twin-prime problem, {II}},
     journal = {Acta Arithmetica},
     pages = {61--89},
     publisher = {mathdoc},
     volume = {13},
     number = {1},
     year = {1967},
     doi = {10.4064/aa-13-1-61-89},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/aa-13-1-61-89/}
}