diff --git a/documentloader/notebook.go b/documentloader/notebook.go
index dda0992..249c463 100644
--- a/documentloader/notebook.go
+++ b/documentloader/notebook.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"fmt"
 	"io"
-	"strings"
 
 	"github.com/hupe1980/golc/integration/nbformat"
 	"github.com/hupe1980/golc/schema"
@@ -75,7 +74,7 @@ func (l *Notebook) Load(ctx context.Context) ([]schema.Document, error) {
 					pageContent += fmt.Sprintf("'%s' cell: '%s'\n, gives error '%s', with description '%s'\n\n", c.CellType, c.Source, eName, eValue)
 				}
 			} else if c.Outputs[0].OutputType == "stream" {
-				output := strings.Join(c.Outputs[0].Text, "")
+				output := c.Outputs[0].Text
 				minOutput := len(output)
 
 				if minOutput > int(l.opts.MaxOutputLength) {
diff --git a/integration/nbformat/nbformat.go b/integration/nbformat/nbformat.go
index 81f0698..84df017 100644
--- a/integration/nbformat/nbformat.go
+++ b/integration/nbformat/nbformat.go
@@ -4,27 +4,111 @@ package nbformat
 import (
 	"encoding/json"
 	"io"
+	"strings"
 )
 
 // Notebook represents a Jupyter Notebook containing multiple cells.
 type Notebook struct {
-	Cells []Cell `json:"cells"`
+	Metadata      Metadata `json:"metadata"`
+	Nbformat      int      `json:"nbformat"`
+	NbformatMinor int      `json:"nbformat_minor"`
+	Cells         []Cell   `json:"cells"`
+}
+
+// Metadata represents the metadata of a Jupyter Notebook.
+type Metadata struct {
+	KernelSpec   KernelSpec   `json:"kernelspec"`
+	LanguageInfo LanguageInfo `json:"language_info"`
+}
+
+// KernelSpec represents the kernel specification in the metadata.
+type KernelSpec struct {
+	Name        string `json:"name"`
+	DisplayName string `json:"display_name"`
+}
+
+// LanguageInfo represents the language information in the metadata.
+type LanguageInfo struct {
+	Name    string `json:"name"`
+	Version string `json:"version"`
 }
 
 // Cell represents a single cell within a Jupyter Notebook.
 type Cell struct {
-	CellType string   `json:"cell_type"`
-	Source   string   `json:"source"`
-	Outputs  []Output `json:"outputs"`
+	CellType string                 `json:"cell_type"`
+	Source   string                 `json:"source"` // Could be []string, but we always convert it to a single string
+	Metadata map[string]interface{} `json:"metadata"`
+	Outputs  []Output               `json:"outputs,omitempty"`
+}
+
+// UnmarshalJSON custom unmarshals a Cell to ensure Source is always a single string.
+func (c *Cell) UnmarshalJSON(data []byte) error {
+	type Alias Cell
+
+	aux := &struct {
+		Source interface{} `json:"source"`
+		*Alias
+	}{
+		Alias: (*Alias)(c),
+	}
+
+	if err := json.Unmarshal(data, &aux); err != nil {
+		return err
+	}
+
+	switch v := aux.Source.(type) {
+	case string:
+		c.Source = v
+	case []interface{}:
+		var lines []string
+		for _, line := range v {
+			lines = append(lines, line.(string))
+		}
+
+		c.Source = strings.Join(lines, "\n")
+	}
+
+	return nil
 }
 
 // Output represents the output of a cell in a Jupyter Notebook.
 type Output struct {
-	ErrorName  string   `json:"ename"`
-	ErrorValue string   `json:"evalue"`
-	Traceback  []string `json:"traceback"`
-	OutputType string   `json:"output_type"`
-	Text       []string `json:"text"`
+	OutputType string                 `json:"output_type"`
+	Text       string                 `json:"text,omitempty"` // Could be []string, but we always convert it to a single string
+	Data       map[string]interface{} `json:"data,omitempty"`
+	Metadata   map[string]interface{} `json:"metadata,omitempty"`
+	ErrorName  string                 `json:"ename,omitempty"`
+	ErrorValue string                 `json:"evalue,omitempty"`
+	Traceback  []string               `json:"traceback,omitempty"`
+}
+
+// UnmarshalJSON custom unmarshals an Output to ensure Text is always a single string.
+func (o *Output) UnmarshalJSON(data []byte) error {
+	type Alias Output
+
+	aux := &struct {
+		Text interface{} `json:"text,omitempty"`
+		*Alias
+	}{
+		Alias: (*Alias)(o),
+	}
+	if err := json.Unmarshal(data, &aux); err != nil {
+		return err
+	}
+
+	switch v := aux.Text.(type) {
+	case string:
+		o.Text = v
+	case []interface{}:
+		var lines []string
+		for _, line := range v {
+			lines = append(lines, line.(string))
+		}
+
+		o.Text = strings.Join(lines, "\n")
+	}
+
+	return nil
 }
 
 // ReadNBFormat reads and parses a Jupyter Notebook from the given io.Reader.