If a dying person was Makdish all his property, and said '100 Zuz in my possession really belongs to Ploni', he is believed even if Ploni has no document.

If a dying person said '100 Zuz in my possession really belongs to Ploni' orphans are believed to say he later remembered he paid it already.

If a dying person said '100 Zuz in my possession really belongs to Ploni' Ploni can collect with a לא מקויים.

המלוה את חבירו בשטר גובה מנכסים משועבדים.

We can collect from an ערב who wrote underneath the signatures of the witnesses.

בכור gets a double share in land collected for his father's debts.