kono siryou ni ha, tizu mo haitte imasu.

に marks the place something is in or inside.
So 資料に入っています would mean is in the materials/document.

Adding は after に gives that location a topic or contrast nuance:

• この資料には = as for this material / in this material
• It can suggest something like at least in this material or in this one, ...

So には is very common when the speaker wants to highlight the location as the topic.

も means also or too.

So 地図も入っています means:

• A map is also included
• There is a map in it too

This implies that the material contains other things as well, and the map is one more item.

Compare:

• 地図が入っています = A map is included
• 地図も入っています = A map is included too

In this sentence, 入っています describes a resulting state, not an action happening right now.

With verbs like 入る (to enter / to go in), the -ている form often means something has entered and is now in that state.

So:

• 入る = to go in / to enter
• 入っている = to be in / to have been placed inside / to be included

Here, 地図も入っています means the map is inside the materials, or has been included.

It does not usually mean the map is currently in the middle of moving into the document.

Yes, 入る often means to enter, but it can also describe something being contained inside something else.

In everyday Japanese, 入っている is often used for:

• things physically inside something
• items included in a package
• contents in a container

Examples:

• かばんに本が入っています。
  A book is in the bag.
• 箱にお菓子が入っています。
  Candy is in the box.
• この資料に地図が入っています。
  This material includes a map.

So in this sentence, it is very natural.

You could say この資料には地図もあります, and it would be understandable, but the nuance is different.

• あります = there is / exists
• 入っています = is inside / is included

So:

• 地図もあります focuses on the existence of the map
• 地図も入っています focuses on the map being contained in the materials

Because the sentence is about what the materials contain, 入っています is more precise and natural.

Japanese often leaves the subject unstated when it is obvious from context.

In この資料には、地図も入っています, the thing being talked about is 地図 as the item that is included, but the sentence does not need an explicit English-style subject like there or it.

A natural English translation might be:

• This material also contains a map.
• There is also a map in this material.

So the sentence is structured differently from English, and that is normal.

資料 can mean several related things depending on context:

• document
• materials
• information packet
• handout
• reference material

So この資料 could be:

• this document
• this handout
• this packet of materials

Japanese often uses a word like 資料 a little more broadly than a single English word would.

The comma in この資料には、地図も入っています。 is mainly for readability and pause.

It helps separate:

• the topic/location part: この資料には
• the main statement: 地図も入っています

Japanese commas are often more flexible than English commas.
The sentence would still be fine without it:

• この資料には地図も入っています。

Yes, absolutely. That is a very natural translation.

Possible translations include:

• This document also contains a map.
• There’s also a map in this material.
• A map is included in this material too.

The exact English wording depends on context, especially how you translate 資料.

If you said この資料に地図が入っています, it would sound more like a neutral statement identifying what is inside:

• There is a map in this material.

With この資料には, the location is more clearly set up as the topic or contrast:

• As for this material, it also contains a map.

So:

• に
  • が pattern: more straightforward description
• には: highlights the location, often with contrast or topic nuance

Both are possible, but には is very natural when introducing or talking about the contents of something.