Ottó Károlyi writes that, "Two or more notes sounded simultaneously are known as a chord," though, since instances of any given note in different octaves may be taken as the same note, it is more precise for the purposes of analysis to speak of distinct "pitch classes". Furthermore, as three notes are needed to define any common chord, three is often taken as the minimum number of notes that form a definite chord. Hence, Andrew Surmani, for example, (2004, p. 72) states, "When three or more notes are sounded together, the combination is called a chord." George T. Jones (1994, p. 43) agrees: "Two tones sounding together are usually termed an "interval", while three or more tones are called a "chord"." According to Monath (1984, p. 37); "A chord is a combination of three or more tones sounded simultaneously," and the distances between the tones are called intervals. However, sonorities of two pitches, or even single-note melodies, are commonly heard as "implying" chords. A simple example of two notes being interpreted as a chord is when the root and third are played but the fifth is omitted. In the key of C major, if the music comes to rest on the two notes G and B, most listeners will hear this as a G major chord.