Missing source in chapter 20

[xrotwang]

I notice that chapter 20 in the online WALS (http://wals.info/chapter/20) is missing a reference in “See … for careful discussion” in the following:

Conflicting evidence is found, for example, in Lakhota (Siouan; North and South Dakota), where the future tense marker -kta is part of the same phonological word as the verb stem with regard to morphophonological rules, but not apparently with regard to syllabification (see for careful discussion).
I consulted the author who says that the hard copy says "See Russell 1999 for careful discussion."

where the reference in the bibliography is:

Russell, Kevin. 1999. The "word in two polysynthetic languages. In T. Alan Hall and Ursula Kleinhenz, eds., Studies on the Phonological Word 203-221. Amsterdam: Benjamins.

I suspect that the source of this may be that this source is not the source for any datapoint.