find 5 more sources and cited about animal testing

I have already wrote a paper about alternatives to animal testing. I already write 2 alternative methods, now Professor asks me to find 5 more sources(need to be cited) to support my method. Plz add another 500 words to it.

For example, why is my method better than other method, and who will support and oppose to my alternatives methods. Plz use the sources to support it

Here is professor’s comment:

Comments:

This is much better. I think you did a good job narrowing things down. Now, I would like more details about the solutions you’ve chosen to include here. More details describing how this testing practices work and why they make sense as replacement tests for current animal models will be necessary. I also want to get a sense of who supports and who opposes these testing practices and why. Why does your solution make the most sense to try out of all the possible alternatives? Spending time with the details of these tests as a way to unpack your argument will help your reader understand the importance of these alternatives.And Plz add 5 more sources to support your methods why is better than other methods and who will support it and oppose to it.