A list of works that the article's author cited. Reading an article in an academic journal usually entails first reading the title, to see if it is related to the desired topic. If it is, the next step is to read the abstract …

This is a list of puzzles that cannot be solved. An impossible puzzle is a puzzle that cannot be resolved, either due to lack of sufficient information, or any number of logical impossibilities.

Echo and Narcissus is a 1903 oil painting by John William Waterhouse. It illustrates the myth of Echo and Narcissus from Ovid 's Metamorphoses. John William Waterhouse (1847–1917) was an English …

In ultrasound systems, lateral resolution is usually much lower than the axial resolution. The poor lateral resolution in the B-mode image also results in poor lateral resolution in flow estimation. Therefore, …

Theories have included claims that Cicada 3301 is a secret society with the goal of improving cryptography, privacy, and anonymity or that it is a cult or religion. [15][16][17] According to …

Defining riddles precisely is hard and has attracted a fair amount of scholarly debate. The first major modern attempt to define the riddle within Western scholarship was by Robert Petsch in 1899, [5] …

A metapuzzle is a puzzle that unites several puzzles that feed into it. For example, five puzzles that had the answers BLACK, HAMMER, FROST, KNIFE, and UNION would lead to the metapuzzle answer …

One example is the famous passage in Phaenomena 783–7 where the word λεπτή 'slender, subtle' occurs as a gamma acrostic and also twice in the text, as well as diagonally in the text and even …