Okada, Hideo (1999), "Japanese", in International Phonetic Association (ed.), Handbook of the International Phonetic Association: A Guide to the Use of the International Phonetic Alphabet, Cambridge University Press, pp. 117–119, ISBN 978-0-52163751-0

Usually transcribed in IPA with ⟨ ɡ̊⟩ or ⟨ ɡ⟩. Contrasts with aspirated form, which is usually transcribed in IPA with ⟨ kʰ⟩ or ⟨ k⟩. See Danish phonologyK" Oxford English Dictionary, 2nd edition (1989); Merriam-Webster's Third New International Dictionary of the English Language, Unabridged (1993); "kay," op. cit. In the International System of Units (SI), the SI prefix for one thousand is kilo-, officially abbreviated as k: for example, prefixed to metre/ meter or its abbreviation m, kilometre or km signifies a thousand metres. As such, people occasionally represent numbers in a non-standard notation by replacing the last three zeros of the general numeral with K, as in 30K for 30,000.

Olson, Kenneth; Mielke, Jeff; Sanicas-Daguman, Josephine; Pebley, Carol Jean; Paterson, Hugh J. III (2010), "The phonetic status of the (inter)dental approximant", Journal of the International Phonetic Association, 40 (2): 199–215, doi: 10.1017/S0025100309990296, S2CID 38504322Jassem, Wiktor (2003), "Polish", Journal of the International Phonetic Association, 33 (1): 103–107, doi: 10.1017/S0025100303001191 Shosted, Ryan K.; Chikovani, Vakhtang (2006), "Standard Georgian" (PDF), Journal of the International Phonetic Association, 36 (2): 255–264, doi: 10.1017/S0025100306002659 Thelwall, Robin (1990), "Arabic", Journal of the International Phonetic Association, 20 (2): 37–41, doi: 10.1017/S0025100300004266, S2CID 243640727

K was brought into the Latin alphabet with the name ka /kaː/ to differentiate it from C, named ce (pronounced /keː/) and Q, named qu and pronounced /kuː/. In the earliest Latin inscriptions, the letters C, K and Q were all used to represent the sounds /k/ and /ɡ/ (which were not differentiated in writing). Of these, Q was used before a rounded vowel (e.g. ⟨EQO⟩ 'ego'), K before /a/ (e.g. ⟨KALENDIS⟩ 'calendis'), and C elsewhere. Later, the use of C and its variant G replaced most usages of K and Q. K survived only in a few fossilized forms such as Kalendae, "the calends". [4]The airstream mechanism is pulmonic, which means it is articulated by pushing air solely with the intercostal muscles and abdominal muscles, as in most sounds. Padgett, Jaye (2003), "Contrast and Post-Velar Fronting in Russian", Natural Language & Linguistic Theory, 21 (1): 39–87, doi: 10.1023/A:1021879906505, S2CID 13470826 The Semitic form may derive from an earlier sign representing a bent hand. Early Greek forms from the island of Thera have some resemblance to the Semitic. The Chalcidic, Etruscan, and Latin forms were identical, and the letter has retained its shape until modern times. The minuscule form k is but a slight adaptation of the majuscule with the point of junction of three strokes lowered and the lower transverse stroke consequently much shortened and moved to the right. A rounded form also appears in handwriting. Landau, Ernestina; Lončarića, Mijo; Horga, Damir; Škarić, Ivo (1999), "Croatian", Handbook of the International Phonetic Association: A guide to the use of the International Phonetic Alphabet, Cambridge: Cambridge University Press, pp. 66–69, ISBN 978-0-521-65236-0