I question the quality of the story.
Apparently is a classic for mushroom consumption in the 70's. Dunno. My uncle had a copy, he gave it to my Mom and since she was open for me to read everything, I read it as a pre-teen.
At the time I grasped very little.
Recently I grabbed a copy of from the local library. Tried to read it but it required too much effort. Like sorcery but not really. The language is Span-glish (what the Americans call Spanish in the USA, a mix of Spanish with English).
If you don't know some basic Spanish you'll end up googling the words meaning in the USA.
My brother told me to read it with a true open mind. Will try again in the future.