Leslie Kish formular or Leslie Fischer's formular? What is the actual nomenclature? Are these names used interchangeably? The Literature isn't helping to clarify at all.
I don't know who Leslie Fischer is, but Leslie Kish's work is the foundation for most of modern approaches to sample size. So, if you use a sample size calculator that is based on his (yes, his) work, no one is likely to question that choice.
Andrew Paul McKenzie Pegman great advice, why bothering with sample size calculations, power considerations, effect sizes of interest, taking into account model complexity or sampling strategies. One size fits all. Shame on all reasearchers who dared to have larger sample sizes, what a waste of ressources and especially money. *irony off*