** April 15 ( Eastern Orthodox liturgics )

** August 15 ( Eastern Orthodox liturgics )

** Lao New Year, or Songkan / Pi Mai Lao, generally celebrated from 13 to 15 April ( Laos )

** Thai New Year, or Songkran, celebrated from 13 to 15 April ( Thailand )

** Zehra Kadriye Katırcıoğlu ( Istanbul 12 March 1929-Istanbul 15 May 2012 ), married Ahmet Cevat Tugay have 4 sons and a daughter

** F-16 A / B Block 15 ( ADF / MLU ) Fighting Falcon

** Germany — voltage change 3 kV DC – 15 kV AC

** West Bay-every 15 minutes, Su-Th 6AM-11PM ; F, Sa 6AM-12AM.

** Chile ( February 15, 2002 )

** Caribbean Community ( CARICOM )¨ ( November 15, 2002 )

** Top Scorer Italian Cup: ( 4 goals ) Total ( 15 goals ) Italian Cup.

** February 15 ( Eastern Orthodox liturgics )

** Retail, accommodation and food services 15. 7 %

** The Battle of Harpers Ferry ( September 12 – 15, 1862 ), a battle in the American Civil War that took place around what is now Harpers Ferry, West Virginia

** NATO Training Mission – Iraq, from 2004 ( Iraq ) – 82 out of 169 soldiers from 15 countries

** Two-pore-domain potassium channels: This family of 15 members form what is known as leak channels, and they follow Goldman-Hodgkin-Katz ( open ) rectification.

** Two-pore-domain potassium channels: This family of 15 members form what is known as leak channels, and they follow Goldman-Hodgkin-Katz ( open ) rectification.

** January 15 ( Eastern Orthodox liturgics )

** June 15 ( Eastern Orthodox liturgics )

** July 15 ( Eastern Orthodox liturgics )

** May 15 ( Eastern Orthodox liturgics )

** Chirp spread spectrum ( CSS ) according to IEEE 802. 15. 4a CSS uses pseudo-stochastic coding

** 15 – 64 years: 58. 7 % ( male 3, 578 ; female 3, 656 )

** under 15 years: 1. 1 male ( s )/ female

** 15 – 64 years: 1. 0 male ( s )/ female

** Eunectes murinus, the green anaconda, the largest species, is found east of the Andes in Colombia, Venezuela, the Guianas, Ecuador, Peru, Bolivia, Brazil and on the island of Trinidad.

** Eunectes notaeus, the yellow anaconda, a smaller species, is found in eastern Bolivia, southern Brazil, Paraguay and northeastern Argentina.

** Eunectes deschauenseei, the dark-spotted anaconda, is a rare species found in northeastern Brazil and coastal French Guiana.

** Eunectes beniensis, the Bolivian anaconda, the most recently defined species, is found in the Departments of Beni and Pando in Bolivia.

** Well-ordering theorem: Every set can be well-ordered.

** Tarski's theorem: For every infinite set A, there is a bijective map between the sets A and A × A.

** Trichotomy: If two sets are given, then either they have the same cardinality, or one has a smaller cardinality than the other.

** The Cartesian product of any family of nonempty sets is nonempty.

** König's theorem: Colloquially, the sum of a sequence of cardinals is strictly less than the product of a sequence of larger cardinals.

** Every surjective function has a right inverse.

** Zorn's lemma: Every non-empty partially ordered set in which every chain ( i. e. totally ordered subset ) has an upper bound contains at least one maximal element.

** Hausdorff maximal principle: In any partially ordered set, every totally ordered subset is contained in a maximal totally ordered subset.

** Tukey's lemma: Every non-empty collection of finite character has a maximal element with respect to inclusion.

** Antichain principle: Every partially ordered set has a maximal antichain.

** Every vector space has a basis.

** Every unital ring other than the trivial ring contains a maximal ideal.

** For every non-empty set S there is a binary operation defined on S that makes it a group.

** The closed unit ball of the dual of a normed vector space over the reals has an extreme point.

** Tychonoff's theorem stating that every product of compact topological spaces is compact.

** In the product topology, the closure of a product of subsets is equal to the product of the closures.

** If S is a set of sentences of first-order logic and B is a consistent subset of S, then B is included in a set that is maximal among consistent subsets of S. The special case where S is the set of all first-order sentences in a given signature is weaker, equivalent to the Boolean prime ideal theorem ; see the section " Weaker forms " below.

** Any union of countably many countable sets is itself countable.