1. Global Strategy for Diagnosis, Management, and Prevention of COPD from the Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2013. http://www.goldcopd.org/ (date last accessed June 1 2016).
2. The Medicines Utilisation Monitoring Centre. National Report on Medicines use in Italy. Year 2014. Rome: Italian Medicines Agency, 2015. http://www.agenziafarmaco.gov.it/sites/default/files/Rapporto_OsMed_2014_0.pdf (date last accessed June 1 2016).
3. Spiriva® Summary of Product Characteristics. Banca dati farmaci. Agenzia Italiana del Farmaco. https://farmaci.agenziafarmaco.gov.it/bancadatifarmaci/ (accessed 1 June 2016).
4. Spiriva® Respimat® Summary of Product Characteristics. Banca dati farmaci. Agenzia Italiana del Farmaco. https://farmaci.agenziafarmaco.gov.it/bancadatifarmaci/ (date last accessed June 1 2016).
5. Call for worldwide withdrawal of tiotropium Respimat mist inhaler;R Beasley;BMJ,2012