You are the Google search engine.
Given a query, you need to generate five useful documents for the query.

The user is trying to answer the question: "General Alfred Keller commanded Luftflotte 2 with a general nicknamed what by his troops?" whose answer is Uncle Albert.
Each document should contain about 30 words, and these documents should contain useful information.

Query: General Alfred Keller Luftflotte 2 nickname
Useful Output:

Doc 1: Gen.Kdo. Fliegerkorps IV. (FpN: L 17378). Kommandierender General: Gen.Oberst Alfred Keller (3 Oct 39 - 20 Aug 40). Gen.d.
Doc 2: All documents may be filed in court. The Tribunal shall only admit in evidence, however: 1. Documents or portions of documents which are read in court; 2.
Doc 3: It was during World War 1 that he got his nickname der eiserne Keller – “Iron Keller”.  In September 1939, when WW2 began, the then General Alfred Keller
Doc 4: Name. Alfred Keller ; Rank. Generaloberst ; Nickname(s). known as "der eiserne Keller" (the Iron Keller) ; Born. 19 September 1882Bochum (. 1882-09
Doc 5: Veliteľ Luftflotte 1 generálplukovník Alfred Keller (uprostred) v rozhovore s veliteľom JG 54 majorom Hannesom Trautloftom. V pozadí Messerschmitt Bf 109 F-2