Question: German invaded Poland during WWII during which years?
About the article "Invasion of Poland", section "Abstract".

Candidate passages:
During WWII, when Nazi army invaded Poland, German military commissar took the control of Giesche Spolka Akcyjna.
SACO was thus deprived of all income from the Spolka properties and was unable to pay dividends on its outstanding bonds.
With the approach of August 1, 1941, the maturity date of the bonds, the company had only about half a million dollars in cash.
Accordingly it filed a petition for reorganization under Chapter X of the Bankruptcy Act. 
Żerków (; German: "Zerkow", 1943–1945 "Bergstadt (Kr.
Jarotschin")) is a town in Jarocin County, Greater Poland Voivodeship, Poland, with 2,076 inhabitants (2004).
Zerkow was used by the Germans during WWII as a resort spot for soldiers during the war, which is located 53 kilometers east of the Polish Industrial City of Poznań, Poland.
In 1962 a telecommunication tower of reinforced concrete similar to that at Piatkowo was built. 
IBM had an office in Shanghai.
When Japan invaded during WWII, they took an IBM machine back to Kobe. 
  April – Holocaust: the Nazi German extermination camp Sobibor opens in occupied Poland on the outskirts of the town of Sobibór.
Between April 1942 and October 1943, at least 160,000 people are killed in the camp.
Spring – Holocaust: the Nazi German extermination camp Treblinka II opens in occupied Poland near the village of Treblinka.
Between July 23, 1942 and October 1943, around 850,000 people are killed there, more than 800,000 of whom are Jews.
April 3 – WWII: Japanese forces begin an all-out assault on the United States and Filipino troops on the Bataan Peninsula.
April 5 – WWII: the Japanese Navy attacks Colombo in Ceylon (Sri Lanka).
Royal Navy Cruisers and are sunk southwest of the island.
April 9 – WWII: * The Bataan Peninsula falls and the Bataan Death March begins.
* The Japanese Navy launches an air raid on Trincomalee in Ceylon (Sri Lanka); the Royal Navy aircraft carrier and Royal Australian Navy destroyer are sunk off the country's East Coast.
April 13 – The United States Federal Communications Commission's minimum programming time required of TV stations is cut from 15 hours to 4 hours a week during the war.
April 14 – WWII: The submarine is sunk.
April 14 – WWII: The German submarine U-85 (1941) is sunk by .
April 15 – WWII: King George VI awards the George Cross to Malta to mark the Siege of Malta, saying, "To honour her brave people I award the George Cross to the Island Fortress of Malta, to bear witness to a heroism and a devotion that will long be famous in history (from January 1 to July 24, there is only one 24-hour period during which no bombs fall on this tiny island)."
April 17 – WWII: Henri Giraud the French commander captured in 1940, escapes from Königstein Fortress.
April 18 – WWII: Tokyo, Japan, is attacked by the Doolittle Raid, a small force of B-25 Mitchell bomber aircraft commanded by then-Lieutenant Colonel James "Jimmy" Doolittle.
April 23 * WWII: Exeter becomes the first historic English city bombed as part of the Baedeker Blitz in retaliation for the British bombing of Lübeck.
* Exeter-born William Temple enthroned as Archbishop of Canterbury.
April 26 – WWII: The Reichstag meets for the last time, dissolving itself and proclaiming Adolf Hitler the "Supreme Judge of the German People", granting him the power of life and death over every German citizen.
April 27 – WWII: A national plebiscite is held in Canada on the issue of conscription.
April 27 – The Jewish Star of David is required wearing for all Jews in the Netherlands and Belgium; Jews in other Nazi-controlled countries have already been wearing it.
April 29 – WWII: An explosion at a chemical factory in Tessenderlo, Belgium leaves 200 dead and 1,000 injured.  
The town of Tykocin was conquered by Nazi Germany during the Soviet and German invasion of Poland pursuant to their secret agreement known as the Molotov–Ribbentrop Pact.
At the end of September 1939, the area was transferred by the Nazis to the Soviet Union in accordance with the German–Soviet Boundary Treaty.
In their attack, the Red Army overrun 52.1% of territory of interwar Poland with over 13,700,000 inhabitants.
The Soviet occupation zone included also 336,000 new refugees who escaped from Polish lands invaded by Germany, most of them Polish Jews numbering at around 198,000.
Spreading terror throughout the region, the Soviet secret police (NKVD) accompanying the Red Army massacred Polish prisoners of war, and in less than two years, deported up to 1.5 million ethnic Poles to Siberia.
Twenty-one months after the Soviet invasion of Poland, during the German Operation Barbarossa in June 1941, the town was overrun again, this time by Wehrmacht followed closely behind by Einsatzgruppen.
The Germans installed Jan Fibich, a local ethnic German, as mayor.
Fibich, aided by Edmund Wiśniewski, prepared a list of Jews collaborating with the Soviet NKVD, which included almost all of Jewish youth.