Is mudarabah permissible when the capital contributed by both parties is mixed (musha')?

Primary text

Mudarabah is permissible when the capital is mixed, provided the mixture occurs with the working partner (al-amil). The prohibition against mixed capital only applies when it is mixed with a partner other than the worker, as such mixture prevents the non-working partner from controlling the disposition of the assets. When mixed with the worker, it does not prevent him from acting, thus the validity of the mudaraba is not affected.