This is an interesting construction. Here's my understanding of this.
- In general, -たい can only be used for something desirous to the speaker. When talking about someone else's desires, -たがる is used instead -- from the basic underlying idea that the speaker cannot truly know what is going on in someone else's head. So the root -たい is suffixed with -がる, meaning "seems like, looks like, behaves like
[whatever came before the suffix]
".
Since the expression in your sample text uses -たい, we know that this is talking about something the author wants.
- されたい is simply される (passive for する) + -たい. In basic literal terms, it means that the speaker wants (the -たい) the action to be done (the される passive).
Applying that to the sample sentence, we get:
巻末付録を参照されたい。
I would like the appendix at the end to be referenced.
In functional terms, this is used as a kind of more polite and indirect way of saying:
巻末付録を参照してほしい。
I want you to reference the appendix at the end.
This latter -てほしい construction is much more direct, and in all languages I've studied, direct statements may be viewed as less polite, perhaps even confrontational, while indirect statements are generally viewed as more polite and less confrontational.
goo's analysis
This may be a quibble, and is more of a deeper-level semantic argument. Beginning learners may want to ignore this section. :)
I confess I don't agree with goo's analysis. If we view the れる here as purely an honorific construction, then the action is still being done by the listener, and the -たい would then apply to an action done by the listener, and would point towards the state of mind of the listener. However, as I've been taught, -たい cannot be used when talking about the state of mind of the listener -- this can only apply to the speaker. This is why I view the される verb in 参照されたい as the passive rather than an honorific.
Viewed either way, as the honorific or the passive, the resulting meaning is the same, so this difference of opinion probably doesn't amount to much. :)