References in classic literature ?
MY BELOVED MAKAR ALEXIEVITCH,--So eager am I to do something that will please and divert you in return for your care, for your ceaseless efforts on my behalf--in short, for your love for me-- that I have decided to beguile a leisure hour for you by delving into my locker, and extracting thence the manuscript which I send you herewith.
Quantitative determination of chemical constituents Extract yield percentage and total phenolic contents: The extraction yield was calculated to determine the effectiveness of the solvents in extracting the active compounds from the plant material.