english.stackexchange.com/questions/121054/which-one-is-correct-et-al-s-or-et-al

The grammatically correct way is "Einstein et al.'s paper", because to indicate possession by a noun phrase in English, the 's should be applied ...

english.stackexchange.com/questions/33304/et-cetera-vs-et-al

I would say there is a definite distinction between the two, in definition and in proper usage. Et cetera, often shortened to etc., means literally ...

grammarist.com/usage/et-al

Jun 21, 2011 ... Et al.is an abbreviation of the Latin loanphrase et alii, meaning and others. It is similar to etc. (short for et cetera, meaning and the rest), but ...

www.e-education.psu.edu/styleforstudents/c3_p28.html

It is important to use these abbreviations literally and to punctuate them correctly. Many writers confuse "e.g." and "i.e.," and many type "et al." improperly or do ...

www.gingersoftware.com/english-online/spelling-book/confusing-words/etc-et-al

Keep using etc. instead of et al.? Check out Ginger's spelling book and make sure you never confuse etc. and et al. again!