Instruction timing expressions references

http://www.anapsid.org/resources/drugdose.html

http://www.d.umn.edu/medweb/Modules/Prescription/Abbreviations.html

https://en.wikipedia.org/wiki/List_of_medical_abbreviations:_Latin_abbreviations

http://petdiabetes.wikia.com/wiki/Dosage_abbreviation

https://argonaut.healthintersections.com.au/datatypes.html#timing

http://www.cwladis.com/math104/lecture5.php

http://wiki.ihe.net/index.php/1.3.6.1.4.1.19376.1.5.3.1.4.7