@article{AMLG_1977__18_137924,
     author = {Yuri Gurevich},
     title = {Semi-conservative recduction.},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {23--26},
     publisher = {mathdoc},
     volume = {18},
     year = {1977},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1977__18_137924/}
}