What is the word describing impossible phenomenon such as "This page [is] intentionally left blank"?

You can find in book's pages a single sentence: This page intentionally left blank. It is interesting to note that this statement is false, since the page contains text.

Here are two (somewhat) similar examples: This is a secret encoded message which you cannot read, comprehend, or make of any sense! (You can read it, and it makes perfect sense); and This is a short description of the Fraser spiral illusion which, like as Zöllner's illusion and the café wall illusion are based on a principle, like many other visual effects, in which a sequence of tilted elements causes the eye to perceive phantom twists and deviation. (This is a lengthy description).

What is the word (maybe a collective noun?) describing such impossible claims/events/phenomena? The closest word I can think of is oxymoron:

A figure of speech in which apparently contradictory terms appear in conjunction (e.g., faith unfaithful kept him falsely true).

However, the problem with oxymoron is that it somehow requires two terms to contradict with each other. Here the text contradicts with itself.

Well, I almost deleted my draft prior post, since it seemed plausible, that this is a self-contradiction:

Inconsistency between aspects or parts of a whole.

However, this (somewhat lengthy) wikipedia talk page suggests that this is not a self-contradiction. A self-contradiction would be a sentence something like: Bob is a married bachelor.

Then what are these sentences called?

Solution 1:

Paradox is likely what you are looking for:

1. a statement or proposition that seems self-contradictory or absurd but in reality expresses a possible truth.
2. a self-contradictory and false proposition.
3. any person, thing, or situation exhibiting an apparently contradictory nature.

(From Dictionary.com)

Solution 2:

Paradox, but more precisely,

Liar paradox

Wikipedia

eg. If "this sentence is false" is true, then the sentence is false, but if the sentence states that it is false, and it is false, then it must be true, and so on.

Dictionary.com

philosophy

A sentence which asserts its own falsity, e.g. "This sentence is false" or "I am lying". These paradoxical assertions are meaningless in the sense that there is nothing in the world which could serve to either support or refute them.

Maybe contradiction, or more precisely,

Performative contradiction

Wikipedia

A performative contradiction (German: performativer Widerspruch) arises when the propositional content of a statement contradicts the presuppositions of asserting it. An example of a performative contradiction is the statement "I am dead" because the very act of proposing it presupposes the actor is alive. Performative contradictions cannot be rationally advanced in argument.

The statement "Don't do as I do, do as I say" is arguably a performative contradiction because its assertion presupposes it being said by an asserter, rendering the two directives contradictory. The statement "Hierarchies do not exist" offers a more subtle example of performative contradiction referring to the very capacity of making a statement, because the statement itself is a hierarchy of semiotic relations of letters (as symbols) formed into words (as signifiers) formed into a sentence (as a statement).

For further reading: List of paradoxes on Wikipedia