Über die Häufigkeit vollkommener Zahlen

@article{Hornfeck1957berDH,
  title={{\"U}ber die H{\"a}ufigkeit vollkommener Zahlen},
  author={Bernhard Hornfeck and Eduard Wirsing},
  journal={Mathematische Annalen},
  year={1957},
  volume={133},
  pages={431-438}
}
Decatizing apparatus comprises a steaming cylinder and a suction cylinder. Respective primary backing cloths are associated with the steaming and suction cylinders to press the fabric to be treated against the cylinders, the tension of each primary backing cloth being adjustable independently of the other backing cloth. An intermediate backing cloth is interposed between each primary backing cloth and the fabric in the zone of the cylinder, and moves over the cylinder with its associated… 

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