De tacitis fideicommissis liber singularis
Dig. 34,9,23Gaius libro singulari de tacitis fideicommissis. Si quilibet heres ex cuiuscumque testamento tacite rogatus fuerit, ut quadrantem, quem legis Falcidiae beneficio retinuit, non capienti restituat, aeque locus erit senatus consulto: neque enim multum intererit inter tale fideicommissum et cum quis id, quod ad se ex hereditate pervenerit, restituere rogatus sit.
Gaius, On Implied Trusts. Where any heir whosoever, having been tacitly requested by the will of a testator to deliver to some person not entitled to receive it a fourth part of the estate to which he is entitled under the Falcidian Law, there will also be ground for the application of the Decree of the Senate; for there is not much difference between a trust of this kind and one where an heir is charged to give property which he has received from an estate to a party who is incapable of receiving it.