Trilateration of a signal using Time Difference of Arrival

Question

I am having some trouble to find or implement an algorithm to find a signal source. The objective of my work is to find the sound emitter position.

To accomplish this I am using three microfones. The technique that I am using is multilateration that is based on the time difference of arrival.

The time difference of arrival between each microfones are found using Cross Correlation of the received signals.

I already implemented the algorithm to find the time difference of arrival, but my problem is more on how multilateration works, it's unclear for me based on my reference, and I couldn't find any other good reference for this that are free/open.

If you have some references on how I can implement a multilateration algorithm, or some other trilateration algorithm that I can use based on time difference of arrival it would be a great help.

Thanks in advance.