"Practical Queen Rearing," book by Charles/Pauline Dublon (Welsh couple),
includes an
in-depth discussion of the SUBJECT line.  Brushy Mountain Bee supplies
in Moravian Falls NC usa (1-800-BEESWAX) was selling it in 1994 for
$17.45 plus 2# shipping (send 4 their free catalog?). Bonne chance.
Jack the B-man
Ellicott City MD usa
PS "It's a pleasure to give advice,
  humiliating to need it,
  and perfectly normal to ignore it."