Have a look at this paper and let me know what you think:
http://em.rdcu.be/wf/click?upn=KP7O1RED-2BlD0F9LDqGVeSN5m1y-2BWwoChMVWjZnRTPr0-3D_-2BPe06-2FbvfIwPZYvDYsJeB9xvfMwjetdydMqrajyGdK1ZS6TCZBPgOmr-2F-2B-2F5MnPHwY-2Ft0T26hIB7tEMkvLyno04kH4io9nOIsBjDHwtzlaw6mZhS8f9Jg8iTuLrXfcw6-2FYL3UEi4p3GqzizMNmBAULzv2KtnB8PR149tdBRPcYvAnu0k9aKVyfBKRRkEHGeJmlgXgWnO-2Fv4-2F-2B1OvXGndKmTpx3px3b1-2BD3kzDInbD-2BWE-3D