Reference for Menachot 179:1

אי לא חזו לעולת חובה קרבי לעולת נדבה אלא הכא אי לא מוקמית ליה במילתיה אשם נדבה מי איכא

and if they are not admissible as the original obligatory burnt-offerings, they are nevertheless admissible as freewill burnt-offerings;<span class="x" onmousemove="('comment',' Accordingly in the circumstances stated, neither the lamb of the 'Omer would require a double meal-offering, nor the daily offerings the special offering of wood, since they could be offered as freewill burnt-offerings.');">¹</span> but here [in the case of the guilt-offering of a leper] if you do not regard it as th originally named [offering, it cannot be offered at all, for] there is no such thing as a freewill guilt-offerin

Jastrow

Jastrow