Determination of fluid category 2. Water in fluid category 1 whose aesthetic quality is impaired owing to: 1  a change in its temperature; or. 2  the presence of substances or organisms causing a change in its taste, odour or appearance, including water in a hot water distribution system.
Credibility is defined as the quality or power of inspiring belief. Credible sources, therefore, must be reliable sources that provide information that one can believe to be true. It is important to use credible sources in an academic research paper because your audience will expect you to have backed up your assertions with credible evidence.
Qualitative research does not require external validity, for each research is unique and has different settings. The validity of qualitative research depends rather on transferability. Transferability is the ability to generalize, or the extent to which the results of the research apply to other contexts or settings. Qualitative research with descriptive research context and assumptions generally has greater transferability compared to research with lesser descriptive contexts and fewer assumptions.