Correct spacing for "Smith et al. (2008)"

Question

An academic paper is referred to as using the authors name and publication year.

For example,

1. Smith (2008) studied the property of blah-blah
2. Smith and Johnson (2013)'s article investigated blah-blah
3. Johnson et al.(2009)'s paper studies blah-blah

Here I wonder what is the correct spacing between the name(s) and year (in the parenthesis) and between year and "'s".

In #1. putting a space between Smith and (2008) looks natural, but in #2, it is weird because there is a space between Johnson and "'s". (Without (2013), it becomes "Johnson 's")

Is there any clear rule or common practice for this?

Answer 1

I'm not entirely sure, but with correct grammar, I'm fairly sure it would be this:

Smith and Johnson's (2013) article investigated blah-blah

Answer 2

That's an annoying construction to punctuate, I agree. You might try:

Smith and Johnson's article (2013) investigated blah blah

The article from Smith and Johnson (2013) investigated blah blah

The paper from Johnson et al. (2013) investigated blah blah

Please note the space between al. and 2013. The al. is short for alia, meaning "others."

In any case, I wouldn't put the apostrophe-S after the year in parens. It looks too weird. Reword until you get the year and possessive apart.