:The ideal ratio is zero - that is, zero first-party references, at least for things that relate to claims of notability.  For academics, it's not always going to happen, but get as close as you can, even if it means greatly reducing the scope and size of the article.  Basically, barring "gotta have it" things like year of birth and year of death, if it's not important enough that someone else has written about it, then it's not important enough to put in Wikipedia.  The article on Nobel-prizewinning immunologist Rolf M. Zinkernagel is on the short end of acceptable for a Nobel-prize-winner but it would be about the right size for a scientist whose contributions to mankind were somewhat less significant.  Notice that, while it actually needs more references, the things that need to be referenced in all but the last paragraph are almost certainly written about in independent, secondary sources.  ///(e-mail)