Plotting Multiple Graphs in MATLAB GUI using a function

I have written a function that returns three plots when one runs the function. I'm having trouble when I'm trying to plot each of these three in three different axes in the MATLAB gui because I do not know what these graphs are stored as in MATLAB to set each figure equal to a specific axes in the GUI window.

I know one can use the set(handles.axes1,...) but I do not know how to use it for three graphs that is run from a function in the GUI.m file and how to catch these files to set them to the appropriate axes.

Thank you in advance for any help