1. For a historical review of the field, see Crystal (1969: Ch. 2). This book, along with its sequel (1975), provides the detailed account of the theoretical frame of reference used in this chapter. The sections below dealing with language acquisition are based on two further papers, ( 1978, 1979b ).
2. As in speech pathology, e.g. Travis (1957: Ch. 22), Greene ( 1964 ). For the phonetic theory underlying the distinction, see Catford (1977). It should be noted that the notion of phonation is also applicable to pitch and loudness features, and is thus less useful for present purposes, where a distinction between these and timbre effects is being maintained.
3. For example, Fries (1964), Crystal ( 1969: Ch. 1). For speech-act, see p. 201.
4. See Quirk, et al.( 1972: Ch. 14), Halliday (1967–1968).
5. For children, see du Preez (1974)