1. J. Potočnik Official Journal of the European Union , 20.10.2011, L275/40
2. the term ‘primary particle’ is defined in ISO 26824: 1.3, Geneva, Switzerland 2013
3. the terms ‘aggregates’ and ‘agglomerates’ are defined in ISO TS 27687
4. a definition of the term ‘constituent particle’ is proposed for ISO DTS 80004-2: 3.3: “ identifyable, integral component of a larger particle (3.1). Note 1 to entry: The constituent particle structures may be original source (primary) particles (3.2) or secondary particles