§ 47-a. Place of filing. An assignment of future earnings or a true copy thereof authenticated by a notary public or commissioner of deeds, together with an itemized statement setting forth the amount then due the assignee and the date and amount of payments theretofore made upon the indebtedness, may be filed in the office of the county clerk of the county in which the assignor resides at the time of the filing thereof, if he resides within the state, and if he resides without the state or his residence is unknown, in the county where the assignor is employed at the time of the filing thereof. If the assignor is employed without the state and his residence is without the state or is unknown, the assignment or authenticated true copy thereof and accompanying statement may be filed in the county where the assignor resided at the time of the execution thereof.