Helping to display a 4D with "isosurface" and "contour3" functions

Hi everyone,

I would like to display a 4D data w=f(x,y,z) using the combination of "isosurface" and "contour3" functions as in the following figure: http://s13.postimage.org/iejhrva7r/Capture.png. I guess this figure is quite popular and its matlab code may be available on the internet. But, I have not found it. So, I would like to know if someone can provide me the code. If not, please give me some ideas to project a isosurface on a plane (e.g., x-y plane). Thank you in advance for help.

Best regards,

Tuan