How to measure peak flow: MedlinePlus Medical Encyclopedia
Peak Expiratory Flow Rate: Purpose, Preparation, and Procedure
Table 2 from Comparison of peak expiratory flow measurement by Mini-Wright peak flow meter and electronic spirometer in healthy elementary school children | Semantic Scholar
7 Best Peak Flow Meters & Tips for Taking Measurements
How to use a peak flow meter
7 Best Peak Flow Meters & Tips for Taking Measurements
Peak Flow Meter: Uses, Procedure, Results
Peak flow chart - National Asthma Council Australia