@article{10_4064_fm_114_2_127_139,
     author = {L. Kirby and K. McAllon and R. Murawski},
     title = {Indicators, recursive saturation and expandability},
     journal = {Fundamenta Mathematicae},
     pages = {127--139},
     publisher = {mathdoc},
     volume = {114},
     number = {2},
     year = {1981},
     doi = {10.4064/fm-114-2-127-139},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/fm-114-2-127-139/}
}