Glasersfeld E. von & Richards J. (1983) The creation of units as a prerequisite for number: A philosophical review. In: Steffe L. P., Glasersfeld E. von, Richards J. & Cobb P. (eds.) Children’s counting types: Philosophy, theory, and application. Praeger, New York: 1–20.

Glasersfeld E. von & Richards J.
(

1983)

The creation of units as a prerequisite for number: A philosophical review.
In: Steffe L. P., Glasersfeld E. von, Richards J. & Cobb P. (eds.) Children’s counting types: Philosophy, theory, and application. Praeger, New York: 1–20.
Glasersfeld E. von, Steffe L. P. & Richards J. (1983) An analysis of counting and what is counted. In: Steffe L. P., Glasersfeld E. von, Richards J. & Cobb P. (eds.) Children’s counting types: Philosophy, theory, and application. Praeger, New York: 21–44.

Glasersfeld E. von, Steffe L. P. & Richards J.
(

1983)

An analysis of counting and what is counted.
In: Steffe L. P., Glasersfeld E. von, Richards J. & Cobb P. (eds.) Children’s counting types: Philosophy, theory, and application. Praeger, New York: 21–44.
Richards J., Steffe L. P. & Glasersfeld E. von (1983) Perspectives and summary. In: Steffe L. P., Glasersfeld E. von, Richards J. & Cobb P. (eds.) Children’s counting types: Philosophy, theory, and application. Praeger, New York: 112–123.

Richards J., Steffe L. P. & Glasersfeld E. von
(

1983)

Perspectives and summary.
In: Steffe L. P., Glasersfeld E. von, Richards J. & Cobb P. (eds.) Children’s counting types: Philosophy, theory, and application. Praeger, New York: 112–123.