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Generate every permutation of a finite list by recursively permuting its tail and inserting its head into each possible position. For distinct input elements, every shorter permutation has insertion positions, giving results. Removing the distinguished head reconstructs the unique shorter permutation and insertion position.
Periodic Table by Royal Society of Chemistry Iodine — Element information, properties and uses by 
Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element information. Cited sections: Fact box, Appearance and Natural abundance. No claim about a particular historical factory recipe is drawn from the modern industrial-source paragraph.
Periodic Table by Royal Society of Chemistry Carbon — Element information, properties and uses by Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element information. Cited sections: Appearance, Uses and descriptions of modern carbon forms.
Periodic Table by Royal Society of Chemistry Caesium — Element information, properties and uses by Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element record. Cited History section: characteristic blue lines and identification in 1860.
Periodic Table by Royal Society of Chemistry Rubidium — Element information, properties and uses by Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element record. Cited History section: identification in 1861 and deep-red spectral features.
Periodic Table by Royal Society of Chemistry Thallium — Element information, properties and uses by Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element record. Cited History section: the green spectral line and 1861 announcement. No biological or medical claim about thallium is drawn from this source here.
Periodic Table by Royal Society of Chemistry Indium — Element information, properties and uses by Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element record. Cited History section: indigo spectral signature and 1863 identification.
Periodic Table by Royal Society of Chemistry Antimony — Element information, properties and uses by Codex 0 2026-10-31
Codex 0 2026-10-31Institutional element record. Cited Appearance, Uses and Natural abundance, including stibnite and alloying uses.
The urogenital triangle is the anterior subdivision of the perineum. It contains the external urogenital openings and associated muscles and membranes. Its name identifies a topographic region; it is not synonymous with the older, anatomically misleading concept of a uniform urogenital diaphragm.
The perineal body is a fibromuscular junction in the perineum where several muscle and connective-tissue elements meet. In female anatomy it lies between the vagina and anal canal. Its value as a support point follows from the convergence of attachments, rather than from being a separate large muscle.
The pudendal canal is a passage in the fascia of obturator internus along the lateral perineal region. It carries the pudendal nerve and internal pudendal vessels. Their common route explains how a local anatomical lesion can affect both neural supply and vascular structures.
The pelvic diaphragm is the muscular floor of the pelvis, formed chiefly by the levator ani group and coccygeus with their associated fascia. It supports pelvic organs while allowing passages for the bowel and urogenital structures. Support and controlled passage must therefore be accommodated by one anatomical arrangement.
An aminopenicillin antibiotic acting on bacterial cell wall synthesis. Susceptibility can be altered by beta-lactamase activity and other mechanisms, separating target chemistry from whole-organism response.
The pubic symphysis is the midline cartilaginous joint between the two pubic bones. It helps maintain continuity of the pelvic ring while allowing limited movement. It is structurally different from the posterior sacroiliac joints.
Excess serum albumin excretion in urine, distinguished from proteinuria due mainly to other proteins.[ref]
Albuminuria: Albumin in the Urine by NIDDK. What is albuminuria?
Excess protein in urine. Glomerular disease, impaired renal tubule recovery and excess circulating small proteins produce different patterns; albuminuria names the albumin component.[ref]
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact