74 Chapter^1
2a. P. Capelli, Sur le nombre complexe binaire, Bull. Amer. Math. Soc., 47 (1941),
585-595.
- C. Caratheodory, Theory of Functions of a Complex Variable, 2 vols., English
edition, Chelsea, New York, 1958-1960. - A. Cayley, Collect. Math. Papers, I, 127.
- C. W. Curtis, The Four and Eight Square Problem and Division Algebras,
Studies in Mathematics, Vol. 2, Mathematical Association of America, 1963. - M. A. B. Deakin, Functions of a dual or duo variable, Math. Mag., 39 (1966),
215-219. - L. E. Dickson, Linear Algebras, Cambridge University Press, Cambridge, 1930.
- L. E. Dickson, On quaternions and their generalizations and the history of the
eight square theorem, Ann. of Math. 20 (1919), - M. Eastham, On the definition of dual numbers, Math. Gaz. 45 (1961), 232.
- F. G. Frobenius, Uber lineare Substitutionen und bilineare Formen, J. Reine
Angew. Math., 84 (1978), 1-63. - H. G. Grassman, Die lineale Ausdehnungslehre, Leipzig, 1844; 2nd ed., 1862.
- L. Gutierrez Novoa, Order characterization of the complex field, Canad. Math.
Bull., 21 (1978), 313-318. - W. R. Hamilton, Lectures on Quaternions, Dublin, 1853.
- A Hurwitz, Uber die Composition der quadratischen Formen von beliebig
vielen Variabeln, Nachrichten der koniglichen Gesellschaft der Wissenschaft,
Gottingen, 1898, 306-316. - M. Itoh, Theory of bicomplex quaternionic and wave-analyti~ functions (ab-
stract), Notices Amer. Math. Soc., 16 (1969), 307; also mimeographed notes,
North Carolina State University (Raleigh). - C. C. MacDuffee, An Introduction to Abstract Algebra, Wiley, New York, 1940.
- J. Milnor, Some consequences of a theorem of Bott, Ann. of Math. 68 (1958),
444-449. - D. H. Moore, Complex number algebra as a simple case of Heaviside
operational calculus, Math. Mag., 43 (1970), 269-272. - R. Nevanlinna and V. Paatero, Introduction to Complex Analysis, Addison-
Wesley, Reading, Mass., 1969. - D. H. Potts, Axioms for complex numbers, Amer. Math. Monthly, 70 (1963),
974-975. - E. Study, Geometrie der Dynamen, Leipzig, 1903.