TopDigitalKnowledge Evidence-only field manuals

What the measurements actually say

Every number in here was measured by somebody

Guides to things people do every day — growing plants, baking bread, sleeping — written the way a paper is written rather than the way a blog post is. Each one states its source count on the cover, cites every one of those sources on the page where it is used, and says plainly where the evidence runs out instead of filling the gap with something that sounds right.

Cited, not “evidence-based”

Every quantity carries a superscript to a numbered source, and the list at the back says what each one actually found.

Figures drawn from the data

No stock photography. Every chart is built from the numbers in the sources, and never claims more than they support.

It says when nobody knows

Each guide lists what could not be supported. Confidence is cheap; knowing which of your habits are load-bearing is not.

Instant download, yours to keep

Print-ready US Letter, and a reflowable EPUB with it on every guide that suits one. No subscription, no expiry. Each product says which.

27 guides

Growing things

Plants, indoors and out. What the measurements say, where the advice is folklore, and which number actually moves the outcome.

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Every guide

All 27, newest first.

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Abdelmounim El Moussaddar

“Every one of these books started with me not believing something, and losing.”

Abdelmounim El Moussaddar

An engineer, and an avid reader and researcher. Writes every guide in this shop.