 Developing Numeracy: Numbers and the Number System: Year 1: Activities for the Daily Maths Lesson (Developings) by Paul Broadbent, 20050803
 The real number system (Wadsworth precalculus mathematics series) by Charles C Carico, 1974
 Number systems: A modern introduction (AddisonWesley series in science and mathematics education) by Mervin Laverne Keedy, 1965
 Modern Basic Mathematics, Number Systems  Structure (Book 1  Teacher's Edition) by Kenneth C. & Edward H. Whitmore Skeen, 1964
 Cambridge Mathematics Direct 4 Numbers and the Number System Pupil's book
 The real number system in an algebraic setting (A Series of undergraduate books in mathematics. Golden Gate books) by Joe Roberts, 1962
 Cambridge Mathematics Direct 6 Numbers and the Number System Teacher's book
 A Development of the Rational Number System; a Programmed Text by Murray Abramson, 19700101
 Maths Plus: Numbers and the Number System by Paul Broadbent, K. Church, et all 19990916
 The personnumber systems of Sweden, Norway, Denmark, and Israel (Vital and health statistics : Series 2, Data evaluation and methods research ; no. 84) by United States, 1980
 How to attain success through the strength of vibration of numbers: A system of numbers as taught by Pythagoras by Sarah Joanna Balliett, 1969
 The Number Crew: Pt. 2: Numbers and the Number System 2  Activity Book by Chris Ellis, Marjorie Gorman, 200008
 A portrait of 2;: A brief survey of the elementary number systems by Lawrence A Ringenberg, 1967
 Cambridge Mathematics Direct 5 Numbers and the Number System Teacher's Handbook
