This part of the Llibre d’estil covers numbers, particularly the question of when they should be written out and what to do if they appear in combination with units of measurement, other numbers and punctuation marks. Although approaches to these issues differ depending on the type of document, these guidelines are intended for institutional rather than technical texts. They also give precedence to British usage, in line with the UB’s preferred spelling system (see Spelling at the UB), although explanations on American usage are given when necessary. For details of using numbers with currencies, see Currencies.