Succah3: 6
עָלְתָה חֲזָזִית עַל רֻבּוֹ, נִטְּלָה פִטְמָתוֹ, נִקְלַף, נִסְדַּק, נִקַּב וְחָסַר כָּל שֶׁהוּא, פָּסוּל.  עָלְתָה חֲזָזִית עַל מִעוּטוֹ, נִטַּל עֻקְצוֹ, נִקַּב וְלֹא חָסַר כָּל שֶׁהוּא, כָּשֵׁר.  אֶתְרוֹג הַכּוּשִׁי פָּסוּל. וְהַיָּרֹק כְּכַרְתִי, רַבִּי מֵאִיר מַכְשִׁיר, וְרַבִּי יְהוּדָה פּוֹסֵל.
If a scab-like boil grew on most of it, [or] its pitam was removed, [or] it was peeled, [or] it was split, [or] it was punctured and is missing a slight portion, it is invalid.  If a boil covered a minority of it, [or] its stem was removed, [or] it was punctured and nothing was missing, it is valid.  An Ethiopian esrog is invalid.  If one is green as a leek, R’ Meir validates it, but R’ Yehudah invalidates it.
Succah3: 7
שִׁעוּר אֶתְרוֹג הַקָּטָן — רַבִּי מֵאִיר אוֹמֵר: כָּאֱגוֹז. רַבִּי יְהוּדָה אוֹמֵר: כַּבֵּיצָה.  וּבַגָּדוֹל — כְּדֵי שֶׁיֹּאחַז שְׁנַיִם בְּיָדוֹ אַחַת; דִּבְרֵי רַבִּי יְהוּדָה. רַבִּי יוֹסֵי אוֹמֵר: אֲפִילּוּ אֶחָד בִּשְׁתֵּי יָדָיו.
The minimum size of an esrog —- R’ Meir says: Like a nut. R’ Yehudah says: Like an egg.  And the maximum —- so that he can hold two [esrogim] in one hand; these are the words of R’ Yehudah. R’ Yose says: Even one [that must be held] in both hands.