hi chemnerd thanks for your positive response and your additional remarks regarding skeletal formulas terminate with ch rather than just the end of a line if one organic chemist like me is communicating with a colleague of the same profession the sketal formulae without an explicit ch is often preferred thats true however i want a broader audience to understand me especially if i write in an encyclopedia this is not only my personal taste please comment on wp csdg general bullets and have a nice weekend thank you