Reference for Zevachim 6:3

כָּל הָעוֹלִים לַמִּזְבֵּחַ, עוֹלִין דֶּרֶךְ יָמִין, וּמַקִּיפִין וְיוֹרְדִין דֶּרֶךְ שְׂמֹאל, חוּץ מִן הָעוֹלֶה לִשְׁלשָׁה דְבָרִים אֵלּוּ, שֶׁהָיוּ עוֹלִים וְחוֹזְרִים לֶעָקֵב:

All who ascend the altar, ascend on the right side, and circle [the altar] and descend on the left side, except those who ascend for these [previously mentioned] three services. They would ascend, and descend by retracing their steps.

Jastrow