"A is followed by B." What's the order?

There's a chance the teacher was explaining how the reference is formatted at the end of the paper. From an IEEE citation reference guide:

Examples:
[1] B. Klaus and P. Horn, Robot Vision. Cambridge, MA: MIT Press, 1986.
[2] L. Stein, “Random patterns,” in Computers and You, J. S. Brake, Ed. New York: Wiley, 1994, pp. 55-70.
[3] R. L. Myer, “Parametric oscillators and nonlinear materials,” in Nonlinear Optics, vol. 4, P. G. Harper and B. S. Wherret, Eds. San Francisco, CA: Academic, 1977, pp. 47-160.

Once you're at the end of the paper (as opposed to in the body of the text), the referencing number is followed by the author's name – just like the teacher said.

_{But your understanding of is followed by is correct.}

A normal use has the name following the reference number when used in the footnote or bibliography.

Chan [1] claims that bound morphemes form an independent class in all PIE-derived languages.

1. Jeremiah P. Chan in “Rethinking morphemic class assignment in Proto-Indo-European” in Proceeding of the American Linguistic Society, June 2015 (Boston).